Renogy 40a mppt Li settings

This is a great thread for those using a lifepro4 with a rover 20/30/40. If others find themselves here I’ve come to learn there are 2 different Bluetooth apps for the rovers. The original was the BT app which had more parameter adjustments in the “user” setting. Renogy no longer updates that app and the BT modules are now meant to be used with the “DC Home” app. When adjusting parameters in the “user” settings your options are a little different.

Equalization Voltage

Boost Voltage

Float Voltage

Low Voltage Reconnect

Low voltage warning

Low voltage disconnect

Boost Duration

I have a brand new lifepo4 that came at 13.3v. I’ve been charging it when I can after work and finally reached up to 14.2v on the battery monitor. Even though my equalization and boost settings were set to the manufacturers specs of 14.4 I started to receive an E02 error which is “Battery Over Voltage” it wasn’t until I moved them down to 13.9 the controller would successfully move from “bulk” to “boost” and then into “float” without setting off any errors.

JPiskun87 said:

I have a brand new lifepo4 that came at 13.3v. I’ve been charging it when I can after work and finally reached up to 14.2v on the battery monitor. Even though my equalization and boost settings were set to the manufacturers specs of 14.4 I started to receive an E02 error which is “Battery Over Voltage” it wasn’t until I moved them down to 13.9 the controller would successfully move from “bulk” to “boost” and then into “float” without setting off any errors.

Click to expand...

Thank you for your contribution and confirming there are two bluetooth apps that can work with the Rover series.

Currently we have a Rover 30 without the BT module, so the USER parameters are very limited. Also, it only allows changes in 0.2V increments. It looks like the BT apps allow for 0.1V increment changes.

I too have a new LFP (Powerurus 200Ah) battery and also have been getting battery over voltage errors with the Rover as the charger. I had had it set at 14.2v (which since the Rover is usually low, actual voltage is probably more like 14.4v) but when I changed it to 14.0v, that seemed to stop the error messages.

I am not physically present with the system (we installed it and my wife left on a trip immediately) so I have not been able to confirm what actual voltage the battery is getting up to during the day or how much a single cell may be out of balance causing the error to trigger before the battery pack reaches the target voltage.

JPiskun87 said:

This is a great thread for those using a lifepro4 with a rover 20/30/40. If others find themselves here I’ve come to learn there are 2 different Bluetooth apps for the rovers. The original was the BT app which had more parameter adjustments in the “user” setting. Renogy no longer updates that app and the BT modules are now meant to be used with the “DC Home” app. When adjusting parameters in the “user” settings your options are a little different.

Equalization Voltage

Boost Voltage

Float Voltage

Low Voltage Reconnect

Low voltage warning

Low voltage disconnect

Boost Duration

I have a brand new lifepo4 that came at 13.3v. I’ve been charging it when I can after work and finally reached up to 14.2v on the battery monitor. Even though my equalization and boost settings were set to the manufacturers specs of 14.4 I started to receive an E02 error which is “Battery Over Voltage” it wasn’t until I moved them down to 13.9 the controller would successfully move from “bulk” to “boost” and then into “float” without setting off any errors.

Click to expand...

While the Renogy DC Home app may work well for you as you say there are some settings not available for the Renogy Rovers that are important in my opinion. The Renogy BT app for the iPhone supports all known settings and was updated about 8 months ago for the iPhone iOS 16 and November 2022 for the android suggesting the app is still supported.

If your solar system has a number of Renogy devices such as smart batteries and inverters along with the Rover the Renogy DC Home app may be the best choice as the Renogy BT app is limited to support for solar charge controllers although I would still probably use the Renogy BT app to program the Rover and then monitor the Rover with the Renogy DC Home app. I do not have any other Renogy solar equipment besides the Rovers in my system and don't use the Renogy DC Home app so this is an educated guess.

The app recently used on my Renogy Rover 40 amp and 100 amp MPPT solar controllers is SRNE utilities. The Renogy Rovers are manufactured by SRNE so the app works good with the Rovers. The app is relatively new and It is well supported with updates coming out every couple of weeks or so. I suggest giving the app a try as it supports all the settings of the Renogy BT app with a nice interface.

Dynoman said:

While the Renogy DC Home app may work well for you as you say there are some settings not available for the Renogy Rovers that are important in my opinion. The Renogy BT app for the iPhone supports all known settings and was updated about 8 months ago for the iPhone iOS 16 and November 2022 for the android suggesting the app is still supported.

If your solar system has a number of Renogy devices such as smart batteries and inverters along with the Rover the Renogy DC Home app may be the best choice as the Renogy BT app is limited to support for solar charge controllers although I would still probably use the Renogy BT app to program the Rover and then monitor the Rover with the Renogy DC Home app. I do not have any other Renogy solar equipment besides the Rovers in my system and don't use the Renogy DC Home app so this is an educated guess.

The app recently used on my Renogy Rover 40 amp and 100 amp MPPT solar controllers is SRNE utilities. The Renogy Rovers are manufactured by SRNE so the app works good with the Rovers. The app is relatively new and It is well supported with updates coming out every couple of weeks or so. I suggest giving the app a try as it supports all the settings of the Renogy BT app with a nice interface.

SRNE

With SRNE Monitoring you can see the real-time data of your devices and configure the settings via Bluetooth. You will also get the insight into our product range and you can test the devices in a DEMO version. Demo Mode: Select a device from the demo library and get an insight of the...

apps.apple.com

SRNE Monitoring - Apps on Google Play

SRNE Monitoring you can see the real-time data

play.google.com

Click to expand...

Just downloaded it, I’ll give it a try. Seems like it allows you to turn equalization off which seems to be nice since it’s not needed with Lifepo4 batteries

Just got the BT-1 Bluetooth dongle for my Rover 30A controller. Installed the DC Home app. Cool thing is the Rover stores data and the app can now read it.

The BAD news is the app reports that the highest battery voltage was once at 17V!! This is for a 12v lifepo4 battery.

The dongle allows you to set different USER settings. Max voltage was default set at 17v, but I thought I had manually set it to an acceptable voltage before I had the dongle. Perhaps once you install the app, it overrides the manually set settings and since I immediately changed them then perhaps nothing bad happened.

My battery was acting very odd for a few hours after installing the renogy Bluetooth dongle. All seems okay now. I’ll update this post if I learn where the odd behavior was coming from. The BMS did turn off the charging MOSFET for a time after connecting the dongle. Maybe this info is listed in this long thread and I missed it, hopefully someone else can avoid my issue.



EDIT: I installed the dongle on 8/21, which is when the issues started, but the app reports the 17v happened on 8/20. Hmph, head scratching…

Tomthumb62 said:

Just got the BT-1 Bluetooth dongle for my Rover 30A controller. Installed the DC Home app. Cool thing is the Rover stores data and the app can now read it.

The BAD news is the app reports that the highest battery voltage was once at 17V!! This is for a 12v lifepo4 battery.

The dongle allows you to set different USER settings. Max voltage was default set at 17v, but I thought I had manually set it to an acceptable voltage before I had the dongle. Perhaps once you install the app, it overrides the manually set settings and since I immediately changed them then perhaps nothing bad happened.

My battery was acting very odd for a few hours after installing the renogy Bluetooth dongle. All seems okay now. I’ll update this post if I learn where the odd behavior was coming from. The BMS did turn off the charging MOSFET for a time after connecting the dongle. Maybe this info is listed in this long thread and I missed it, hopefully someone else can avoid my issue.

View attachment 164024

EDIT: I installed the dongle on 8/21, which is when the issues started, but the app reports the 17v happened on 8/20. Hmph, head scratching…

Click to expand...

It is possible that the battery BMS went into overvoltage protection. This can cause the Rover voltage to momentarily spike high before it is able to correct.

Suggest using the Renogy BT app (See message #24 for link) to program the Rover as some settings are not available in the Renogy DC Home app. Lately the SRNE app has been showing some promise (See message #43 for link). I have been using both apps on my phone.

Dynoman said:

It is possible that the battery BMS went into overvoltage protection. This can cause the Rover voltage to momentarily spike high before it is able to correct.

Suggest using the Renogy BT app (See message #24 for link) to program the Rover as some settings are not available in the Renogy DC Home app. Lately the SRNE app has been showing some promise (See message #43 for link). I have been using both apps on my phone.

Click to expand...

Thanks. I first tried the Renogy BT app and set the settings. Then I tried the DC Home app and you’re right, it only allows changing of a few parameters.

Calling @Renogy Solar , can you explain why my Renogy 30A Rover charge controller tried charging up to 17-18V to my lifepo4 battery? See attached screenshots, taken from the Renogy BT and DC Home apps.

It seems that the default USER settings allow for a “High Voltage disconnect” of 17.0V. This setting isn’t accessible on the front panel buttons on the controller, nor through the DC Home app. It’s only available via the outdated Renogy BT app. I didn’t know this and ran the system for 6 weeks before buying the BT-1 Bluetooth dongle, installing said app and viewing the history to discover what has been happening. I’ve since changed the settings via the app.

Renogy, can you help me understand why this happened?







The battery BMS engaged charging protection several times during the past 6 weeks. I wasn’t physically present to discover the problem earlier but my wife says she saw such protection messages on the BMS app several times. I’m really hoping that the battery isn’t damaged.

Tomthumb62 said:

Thanks. I first tried the Renogy BT app and set the settings. Then I tried the DC Home app and you’re right, it only allows changing of a few parameters.

Calling @Renogy Solar , can you explain why my Renogy 30A Rover charge controller tried charging up to 17-18V to my lifepo4 battery? See attached screenshots, taken from the Renogy BT and DC Home apps.

It seems that the default USER settings allow for a “High Voltage disconnect” of 17.0V. This setting isn’t accessible on the front panel buttons on the controller, nor through the DC Home app. It’s only available via the outdated Renogy BT app. I didn’t know this and ran the system for 6 weeks before buying the BT-1 Bluetooth dongle, installing said app and viewing the history to discover what has been happening. I’ve since changed the settings via the app.

Renogy, can you help me understand why this happened?

View attachment 164114

View attachment 164116

View attachment 164117

The battery BMS engaged charging protection several times during the past 6 weeks. I wasn’t physically present to discover the problem earlier but my wife says she saw such protection messages on the BMS app several times. I’m really hoping that the battery isn’t damaged.

Click to expand...

Suggest revisiting message # 24 of this thread.
In particular lower your Boost Charge Volt(V) to 14.0 volts and your Charge Limit Voltage(V) to 14.1 Volts. The Boost Charge Volt setting is the voltage the controller changes from MPPT (Bulk) Constant Current (CC) charging to Constant Voltage (CV) charging. The Charge Limit Voltage is the maximum voltage the Rover will charge to before the controller goes to 0 amps charging.

Also start with a Boost Charge Time(Min) of 10 Minutes.

If the BMS still goes into over voltage while the controller is in boost lower both the Boost Charge Volt and Charge Limit Voltage. Keep the Charge Limit Voltage 0.1 volts above Boost Charge Volt.

Need to have the Boost Charge Volt, Charge Limit Voltage and Boost Charge Time settings that allow the Rover to transition from Boost to Float without the BMS going into overvoltage.

Need to make changes to the settings and be able to observe what happens during MPPT, Boost and Float. Especially during Boost before transition to float when a BMS overvoltage is possible. Once the system has been observed working properly for a period of time it can be left in auto pilot so to speak, but still needs to be checked now and then in my opinion.

More than likely the BMS has done its job and protected the battery, but the BMS is the fail safe so to speak so need to get the settings correct so that the controller transitions from boost into float and the BMS does not go into over voltage.

Again It is possible that when the battery BMS went into overvoltage protection this caused the Rover voltage to momentarily spike high before it was able to correct. This could cause the 17 volt history readings on the Rover with a 17 volt High Volt Disconnect, but the battery would not see this 17 high voltage because the BMS has disconnected charging from the Rover. So in theory the Rover saw 17 volts, but the battery did not.

What battery do you have?

The High Volt Disconnect(V)14.5 should never happen in a properly programmed Rover with the Boost Charge Volt(V) and Charge Limit Voltage(V) with Boost Charge Time(Min) configured correctly so the BMS does not go into overvoltage.

Please list your Rover Configuration setting as shown by the BT app or better yet post pictures of your settings.

Dynoman said:

Suggest revisiting message # 24 of this thread.

Renogy 40a mppt Li settings

Thanks for the info, I get no heat from the 2 awg wire so that's good for me. Just ordered a 40a circuit breaker to go between the charge controller and batteries plus the Blue Sea 5191 terminal block and 200a fuse today. The 8 guage is less than 2 feet and I did find a little heat when the...

diysolarforum.com

In particular lower your Boost Charge Volt(V) to 14.0 volts and your Charge Limit Voltage(V) to 14.1 Volts. The Boost Charge Volt setting is the voltage the controller changes from MPPT (Bulk) Constant Current (CC) charging to Constant Voltage (CV) charging. The Charge Limit Voltage is the maximum voltage the Rover will charge to before the controller goes to 0 amps charging.

Also start with a Boost Charge Time(Min) of 10 Minutes.

If the BMS still goes into over voltage while the controller is in boost lower both the Boost Charge Volt and Charge Limit Voltage. Keep the Charge Limit Voltage 0.1 volts above Boost Charge Volt.

Need to have the Boost Charge Volt, Charge Limit Voltage and Boost Charge Time settings that allow the Rover to transition from Boost to Float without the BMS going into overvoltage.

Need to make changes to the settings and be able to observe what happens during MPPT, Boost and Float. Especially during Boost before transition to float when a BMS overvoltage is possible. Once the system has been observed working properly for a period of time it can be left in auto pilot so to speak, but still needs to be checked now and then in my opinion.

More than likely the BMS has done its job and protected the battery, but the BMS is the fail safe so to speak so need to get the settings correct so that the controller transitions from boost into float and the BMS does not go into over voltage.

Again It is possible that when the battery BMS went into overvoltage protection this caused the Rover voltage to momentarily spike high before it was able to correct. This could cause the 17 volt history readings on the Rover with a 17 volt High Volt Disconnect, but the battery would not see this 17 high voltage because the BMS has disconnected charging from the Rover. So in theory the Rover saw 17 volts, but the battery did not.

What battery do you have?

The High Volt Disconnect(V)14.5 should never happen in a properly programmed Rover with the Boost Charge Volt(V) and Charge Limit Voltage(V) with Boost Charge Time(Min) configured correctly so the BMS does not go into overvoltage.

Please list your Rover Configuration setting as shown by the BT app or better yet post pictures of your settings.

Click to expand...

THANK YOU! I’m sorry I had missed or forgotten this information as I think it was a few months ago that I had read through the entire thread. This makes a lot of sense. I changed the boost to 14.0v and max charge to 14.1v as you suggested. Hopefully this is the end of the voltage spikes.

One question: what does the boost time (minutes) mean? If I set it for 10 minutes, does it mean it will only go in to boost mode for 10 minutes, then reassess? And I’m guessing the short 10 minute time makes it easier to sit and watch or go through boost/absorb/float cycles? My battery manufacturer recommends a boost/bulk time of 120 minutes.

What battery do you have?

Click to expand...

I have a 12v 200ah Powerurus. I wrote them and asked if they thought my battery has been damaged by the voltage spikes. They said that if the battery is behaving normally, then the BMS is likely fine, but to limit the instances of spikes to occasional or none.

So in theory the Rover saw 17 volts, but the battery did not.

Click to expand...

I hope this is the case! I now wish I had some kind of external monitoring system that could record every second of the battery voltage, read at the terminals.

Please list your Rover Configuration setting as shown by the BT app or better yet post pictures of your settings.

Click to expand...

Tomthumb62 said:

THANK YOU! I’m sorry I had missed or forgotten this information as I think it was a few months ago that I had read through the entire thread. This makes a lot of sense. I changed the boost to 14.0v and max charge to 14.1v as you suggested. Hopefully this is the end of the voltage spikes.

One question: what does the boost time (minutes) mean? If I set it for 10 minutes, does it mean it will only go in to boost mode for 10 minutes, then reassess? And I’m guessing the short 10 minute time makes it easier to sit and watch or go through boost/absorb/float cycles? My battery manufacturer recommends a boost/bulk time of 120 minutes.



I have a 12v 200ah Powerurus. I wrote them and asked if they thought my battery has been damaged by the voltage spikes. They said that if the battery is behaving normally, then the BMS is likely fine, but to limit the instances of spikes to occasional or none.



I hope this is the case! I now wish I had some kind of external monitoring system that could record every second of the battery voltage, read at the terminals.



View attachment 164322
View attachment 164323

Click to expand...

One question: what does the boost time (minutes) mean? If I set it for 10 minutes, does it mean it will only go in to boost mode for 10 minutes, then reassess? And I’m guessing the short 10 minute time makes it easier to sit and watch or go through boost/absorb/float cycles? My battery manufacturer recommends a boost/bulk time of 120 minutes.

Copied from previous message of a Typical Rover Charge Sequence:
When the day starts in the morning the Rover will enter MPPT charge mode and stay there until Boost Charge Volt(V) is obtained. The Rover will stay at Boost voltage for the Boost Charge Time(Min) setting. After Boost Charge Time has completed the Rover will go to Float Charge Volt(V) and stay at this voltage as long as there is enough sunlight to hold the Float voltage setting. If clouds build or if the sun starts to go down (dropping the battery voltage) the Rover will re-enter Boost mode at the Boost Char Return Volt(V). When the battery voltage goes below the Boost Char Return Volt (V) the Rover will go to MPPT charge mode. When night arrives the Rover will go into Nighttime mode with moon icon displayed and will not charge the battery. During Nighttime mode the loads will pull down the battery voltage. When morning comes the cycle repeats.
Note: The Rover should stay in MPPT charge mode if the battery voltage does not reach Boost Charge Volt.

The Boost Charge Time is the time the Rover will stay in boost before transitioning to Float. Suggest starting with 10 minutes to ensure the Rover successful transitions from MPPT to Boost to Float without BMS overvoltage. Once the proper sequence is observed the Boost Time can be increased.

Bulk and boost are different charge modes. Bulk (MPPT displayed on Rover) is constant current where the Rover is charging the battery with the maximum possible current. I have had my Rovers in Bulk charge mode for several weeks before and never reaching the boost voltage level because the loads are consuming all the power the solar panels can make. This happens more in the winter. Often in the summer when there is plenty of sunshine my system runs as described by the Typical Rover Charge Sequence above. So the Bulk charge time is variable.

Boost (also called absorb) is Constant Voltage charging were the voltage is held at a value as the current tapers toward 0 amps, but not reaching 0 amps. On the Rover this is a timed charge mode called Boost Charge Time (minutes)

One of the best indicators the battery is fully charged (or nearly fully charged) is each cell in the battery reaches 3.5 to 3.55 volts and hold it there in Constant Voltage charging mode (Boost, Absorb) until the charging current (Tail Current) drops to 4 or 5%. Tail Current is expressed as a percent of the battery Amp Hour (AH) rating. A 200 AH battery tail current of 5% would be 10 amps (200 x .05 = 10).

A 12 volt Lifepo4 battery has 4 cells (4 x 3.55 = 14.2 volts). When the battery charging goes from Constant Current (Bulk) to Constant Voltage (Boost) at 14.2 Volts the battery voltage is held at about 14.2 volts until the tail current flowing into the battery is about 4 or 5% before transitioning to Float. It is probably OK to leave in boost for 10 minutes or so past reaching the tail current, but probably not much unless trying to balance poorly Top Balanced cells.

Use this Tail Current information to help setting Boost time. My system is in Boost for approximately 20 minutes at 28.5 volts (24 volt system) measured at the battery and this works well most of the time. In the rare event the cells need more balancing may run the boost 30 to 40 minutes max before transitioning to Float.

I have a 12v 200ah Powerurus.

Click to expand...

Looks like a good battery with Bluetooth BMS.

I hope this is the case! I now wish I had some kind of external monitoring system that could record every second of the battery voltage, read at the terminals.

My system uses a Victron BMV-712 smart shunt to monitor the battery. It has Bluetooth to monitor, but it is also sent through a Raspberry pi WiFi to the Victron VRM portal that allows monitoring anywhere on a web browser.

Your Rover Configuration setting as shown by the BT app look like a good place to start. Over time you will find the best settings for your system.

Dynoman said:

One question: what does the boost time (minutes) mean? If I set it for 10 minutes, does it mean it will only go in to boost mode for 10 minutes, then reassess? And I’m guessing the short 10 minute time makes it easier to sit and watch or go through boost/absorb/float cycles? My battery manufacturer recommends a boost/bulk time of 120 minutes.

Copied from previous message of a Typical Rover Charge Sequence:
When the day starts in the morning the Rover will enter MPPT charge mode and stay there until Boost Charge Volt(V) is obtained. The Rover will stay at Boost voltage for the Boost Charge Time(Min) setting. After Boost Charge Time has completed the Rover will go to Float Charge Volt(V) and stay at this voltage as long as there is enough sunlight to hold the Float voltage setting. If clouds build or if the sun starts to go down (dropping the battery voltage) the Rover will re-enter Boost mode at the Boost Char Return Volt(V). When the battery voltage goes below the Boost Char Return Volt (V) the Rover will go to MPPT charge mode. When night arrives the Rover will go into Nighttime mode with moon icon displayed and will not charge the battery. During Nighttime mode the loads will pull down the battery voltage. When morning comes the cycle repeats.
Note: The Rover should stay in MPPT charge mode if the battery voltage does not reach Boost Charge Volt.

The Boost Charge Time is the time the Rover will stay in boost before transitioning to Float. Suggest starting with 10 minutes to ensure the Rover successful transitions from MPPT to Boost to Float without BMS overvoltage. Once the proper sequence is observed the Boost Time can be increased.

Bulk and boost are different charge modes. Bulk (MPPT displayed on Rover) is constant current where the Rover is charging the battery the maximum possible current. I have had my Rovers in Bulk charge mode for several weeks before and never reaching the boost voltage level because the loads are consuming all the power the solar panels can make. This happens more in the winter. Often in the summer when there is plenty of sunshine my system runs as described by the Typical Rover Charge Sequence above. So the Bulk charge time is variable.

Boost (also called absorb) is Constant Voltage charging were the voltage is held at a value as the current tapers toward 0 amps, but not reaching 0 amps. On the Rover this is a timed charge mode called Boost Charge Time (minutes)

One of the best indicators the battery is fully charged (or nearly fully charged) is each cell in the battery reaches 3.5 to 3.55 volts and hold it there in Constant Voltage charging mode (Boost, Absorb) until the charging current (Tail Current) drops to 4 or 5%. Tail Current is expressed as a percent of the battery Amp Hour (AH) rating. A 200 AH battery tail current of 5% would be 10 amps (200 x .05 = 10).

A 12 volt Lifepo4 battery has 4 cells (4 x 3.55 = 14.2 volts). When the battery charging goes from Constant Current (Bulk) to Constant Voltage (Boost) at 14.2 Volts the battery voltage is held at about 14.2 volts until the tail current flowing into the battery is about 4 or 5% before transitioning to Float. It is probably OK to leave in boost for 10 minutes or so past reaching the tail current, but probably not much unless trying to balance poorly balanced cells.

Use this Tail Current information to help setting Boost time. My system is in Boost for approximately 20 minutes at 28.5 volts (24 volt system) measured at the battery and this works well most of the time. In the rare event the cells need more balancing may run the boost 30 to 40 minutes max before transitioning to Float.


Looks like a good battery with Bluetooth BMS.

I hope this is the case! I now wish I had some kind of external monitoring system that could record every second of the battery voltage, read at the terminals.

My system uses a Victron BMV-712 smart shunt to monitor the battery. It has Bluetooth to monitor, but it is also sent through a Raspberry pi WiFi to the Victron VRM portal that allows monitoring anywhere on a web browser.

Your Rover Configuration setting as shown by the BT app look like a good place to start. Over time you will find the best settings for your system.

Click to expand...

Thank you again, Dynoman, for taking the time to explain all of that in just the kind of detail I can understand. The charging cycle explanation really helps me understand what the Rover is doing and why. I’m used to the terms of bulk/absorb/float and Renogy’s use of MPPT/boost/float really confused the heck out of me until your post here.

I will keep an eye on this new setup and see how it goes.

I was about to toss this Rover but maybe it’s worth keeping for now.

I like the Victron stuff, but I’m not thrilled that they require a minimum of 5V over my charging voltage, and since I’m in 4P or 6P (no series), my voltage is barely or not always 5V over the charge voltage.

Dynoman said:

Welcome to the forum!

According to Chins website the specifications are as follows for 1 battery. Some of the values will be different since I assume there are 4 cells in parallel?
Rated Capacity (0.2C): 100Ah / 1280Wh
Cycle life: 2000+ cycles at 80% discharge depth
Rated voltage: 12.8V
Charge voltage: 14.2 - 14.4V
Depth of Discharge (DoD): 100%
Standard charge current: 20A
Charging time: Approximately 6 hours
Max continuous charge current: 50A
Max continuous discharge current: 100A
Peak discharge current: 300A (Duration: less than 5 seconds)
Operating temperatures: Charge 0°C~50°C(32°F~122°F),
Discharge -20°C~60°C(-4°F~140°F), Storage -10~35℃(14℉~95℉)
Impedance: ≤ 10mΩ

14.4v is on the high side for charging your cells. 14.2v would be a safer boost voltage although I use 14.0 because the Renogy Rover I have can read at least 0.1 volt low. Renogy Rover's are know to read voltage low.

Do you have the Renogy Rover 40 amp Mppt Solar Charge Controller?

If you have the Renogy Rover 40 amp Mppt Solar Charge Controller, the LI settings are to aggressive for Lifepo4 Batteries.
Here are the settings used on my Renogy Rover 40 amp
Set to USR & set:
High Voltage Disconnect 14.5v
Charge Limit Voltage14.1v
Equalization Charge Voltage 14.0v
Boost Charge Voltage 14.0v
Float Charge Volt 13.6v
Boost Char Return Volt 13.3v
Over Disc Return Volt 11.0v
Low voltage Alarm 10.9v
Over Discharge Volt 10.5v
Discharge Limit Volt 10v
Over Disc Delay Time 5s
Equalization Charge Time 0 Min
Boost Time 10 Min
Equalize Charge Interval 185 (Note this value cannot be 0 because controller will get stuck in boost mode)
Temp Comp 0A

Unplug temp sensor from the Renogy 40 amp Solar Charge Controller. It is for lead acid and not Lifepo4.

These settings should get you started. You can adjust from there.

I use the Renogy BT-1 Bluetooth Module that plugs in the Rover 40 Rs232 port.
www.amazon.com/Renogy-Bluetooth-Module-Communication-Controllers/dp/B0894SDTSL

With that Module I use the Renogy BT App loaded on my phone to program the settings and monitor the Rover 40 and is free.

‎Renogy BT

‎APP for solar charge controller operation in smart PV power system. It's for solar charge controller working parameter setting and reading. All data can be displayed in a diagram. Meet the Renogy BT. a convenient way to manage and monitor your solar power system all in the palm of your hand...

apps.apple.com

Renogy BT - Apps on Google Play

a convenient way to manage and monitor your solar power system

play.google.com

I hope this helps.

Click to expand...

I have the Renogy 60A controller and it goes to float too soon. My lithium battery pack shows 70% SOC while the Renogy shows 100% and is in float. I am using your suggested settings.

I agree that the renogy setting for lithium seem high. What setting(s) tell the Renogy to go from Boost to float? Is Boost time the only one. In float the renogy outputs about 18 amps while it outputs 55 amps in boost mode.

Frank Smith said:

My lithium battery pack shows 70% SOC while the Renogy shows 100% and is in float.

Click to expand...

You can 100% ignore the SOC reading on the Renogy charge controller. It’s useless.

Your battery pack is likely to be more accurate, assuming it gets calibrated on some sort of regular basis.

If you want the most accuracy of your SoC, then get something like a Victron Smartshunt.

Personally, I don’t use an external shunt like the Smartshunt and instead rely upon the battery’s BMS SoC reading. After some experience with it, it seems to be “close enough”. Close enough might actually mean anywhere from 3-30% off and I’m okay with that. I can’t exactly know how of it actually is without an external shunt. Others have tested theirs with an external shunt and found the BMS (and not all BMS’s are equal) to be fairly accurate, about 1-3% variance. Recalibrating my BMS every so often helps keep it more accurate.

Tomthumb62 said:

You can 100% ignore the SOC reading on the Renogy charge controller. It’s useless.

Your battery pack is likely to be more accurate, assuming it gets calibrated on some sort of regular basis.

If you want the most accuracy of your SoC, then get something like a Victron Smartshunt.

Personally, I don’t use an external shunt like the Smartshunt and instead rely upon the battery’s BMS SoC reading. After some experience with it, it seems to be “close enough”. Close enough might actually mean anywhere from 3-30% off and I’m okay with that. I can’t exactly know how of it actually is without an external shunt. Others have tested theirs with an external shunt and found the BMS (and not all BMS’s are equal) to be fairly accurate, about 1-3% variance. Recalibrating my BMS every so often helps keep it more accurate.

Click to expand...

Thanks.

I am trying to get the batteries charged as full as possible without overcharging them. I am trying to tune the charge controller to do this using Dynoman's settings. The BMS said 96% SOC. I agree the BMS is likely more accurate. Earlier before I tweaked the settings the batteries were getting 8 amps(very low) and the SOC was 78%. After several changes, the boost charge voltage is 14.2 instead of 14 with all the other settings as Dynoman suggests. I'm watching it to be sure it doesn't overcharge.

When the BMS says 90% charged, does that mean 90% of the total battery capacity or 90% of the 95% of capacity that the BMS is set to shut down at.

Frank Smith said:

I am trying to get the batteries charged as full as possible without overcharging them. I am trying to tune the charge controller to do this using Dynoman's settings.

Click to expand...

You cannot overcharge the batteries, because that's what the BMS is for. If the battery gets to the point of being as full as it safely can (it might not reach 100% due to imbalanced cells, a common problem with LFP batteries), the BMS charge protection will kick in and turn OFF charging in the BMS. However, this charge protection is meant to be used for emergencies to protect the battery from catastrophic failure, not as a method to deal with improper charge settings.

If the charge settings are too high (too high of voltage, ie, I have my charge controller set for 14.0V for boost/absorb), then the BMS protection will get kicked on every completed charge cycle. The BMS has a limited number of times the protection will work before the BMS is toast. So this is why it's important to get your charge settings "just right" so you can get as much charge as possible without triggering charge protection in the BMS.

Frank Smith said:

The BMS said 96% SOC. I agree the BMS is likely more accurate. Earlier before I tweaked the settings the batteries were getting 8 amps(very low) and the SOC was 78%.

Click to expand...

Getting 8 amps has nothing to do with your charge settings. Amps is all about how much sun your panels are getting and what the rating of your charge controller is. For example, if your charge controller is a 30A model, then the maximum amount of amps it can supply to your batteries is 30A. You'll likely never see that amount, unless you have sun conditions to be just perfectly right and have enough panels to support that. So if you were only getting 8A and usually see more than that, most likely it was due to the amount of sun (or lack thereof) you were getting at the moment.

Frank Smith said:

After several changes, the boost charge voltage is 14.2 instead of 14 with all the other settings as Dynoman suggests. I'm watching it to be sure it doesn't overcharge.

Click to expand...

Yes, this sounds good. If BMS charge protection doesn't trigger at 14.0V, then you can try a slightly higher voltage. So if you aren't getting BMS charge protection kicking in at 14.2V, then that's a very good sign that the cells in your battery are fairly well-balanced. Very very rarely can LiFePO4 batteries be charged fully to the 14.6V maximum and not trigger the BMS charge protection. It requires an extremely balanced battery to achieve that (took me a long time to understand that one!)

Frank Smith said:

When the BMS says 90% charged, does that mean 90% of the total battery capacity or 90% of the 95% of capacity that the BMS is set to shut down at.

Click to expand...

It means 90% capacity of the total battery capacity. Remember that these bluetooth-enabled BMS's give you an estimate of the SOC, but it's far more reliable the the (totally unreliable) reading that your Renogy Rover will give you.

Rant warning!
=========
Finally, I will say that I had a Renogy Rover 30A for about 4 years. It was a PITA to use. The user interface and the associated app(s) were so poorly designed that it came down to that I couldn't trust that the Rover wasn't damaging (or trying to) my expensive LiFePO4 battery. The settings wouldn't hold when I saved them...or at least it appeared they didn't hold (some people told me they were held even though the app showed me otherwise). I finally sold the damn thing and bought a Victron 100/30 to replace it. It's a night and day difference. Not only was the Victron a breeze to program, I TRUST that it isn't damaging my battery. I also see at least a 15% increase in solar production vs the Renogy, presumably due to it's faster MPPT tracking methods. Victron has lowered their price as well...in fact the Victron model is $27 cheaper!! (source: Renogy Rover 30 is $109+$30 Bluetooth dongle on Amazon, Victron has BT built-in).

I've since sold ALL my Renogy gear (except for a couple of panels) on ebay or craigslist. They were easy to sell because the average beginner solar consumer's perception of Renogy is a positive one. They do work, sort of, just poorly and inefficiently and are not a good bargain considering how much headache their products and customer service have given me.

Frank Smith said:

I have the Renogy 60A controller and it goes to float too soon. My lithium battery pack shows 70% SOC while the Renogy shows 100% and is in float. I am using your suggested settings.

I agree that the renogy setting for lithium seem high. What setting(s) tell the Renogy to go from Boost to float? Is Boost time the only one. In float the renogy outputs about 18 amps while it outputs 55 amps in boost mode.

Click to expand...

If the battery pack is Lifepo4 and using the USER settings with a Renogy Rover and the voltage is at 14.0 volts or more (Measured at the Battery) the battery should be in what's called the upper knee of the charge curve and approximately 97% or more charged.

As you suggest the Boost time is the setting to hold at Boost voltage before going to Float voltage and the only setting. It is the amount of time the Rover will hold the Boost Constant Voltage charge before going to the Float Constant Volt mode.

55 amps is a good charge rate in Boost, but should see the current decrease once boost starts. During Boost the charge current should decrease (tail) towards zero, but not reach zero. A Tail current of 4 or 5% when at the end of Boost is considered a nearly or fully charged battery. So at the end of the Boost Time the current in a 100ah battery should be around 4% 100ah x .04 = 4 amps. If at the end of the Boost Time the current has not decreased to around 4 or 5% increase the boost time until the current is around 4 or 5%. Note that I now charge to about 28.4 volts measured with Victron Smart Battery Monitor (24 volt system) for about 20 minutes and sometimes the boost current will be a low as 2 or 3 %.

The Float charge current to the battery should be near zero once the voltage has stabilized (13.5V) in float mode for 30 minutes or so. Around 30 minutes the charge to my battery bank is usually less than 1 amp and will continue to decrease. After and hour or 2 in float the current is usually bouncing + and - 0 amps.

Hope this helps...

Tomthumb62 said:

You cannot overcharge the batteries, because that's what the BMS is for. If the battery gets to the point of being as full as it safely can (it might not reach 100% due to imbalanced cells, a common problem with LFP batteries), the BMS charge protection will kick in and turn OFF charging in the BMS. However, this charge protection is meant to be used for emergencies to protect the battery from catastrophic failure, not as a method to deal with improper charge settings.

If the charge settings are too high (too high of voltage, ie, I have my charge controller set for 14.0V for boost/absorb), then the BMS protection will get kicked on every completed charge cycle. The BMS has a limited number of times the protection will work before the BMS is toast. So this is why it's important to get your charge settings "just right" so you can get as much charge as possible without triggering charge protection in the BMS.


Getting 8 amps has nothing to do with your charge settings. Amps is all about how much sun your panels are getting and what the rating of your charge controller is. For example, if your charge controller is a 30A model, then the maximum amount of amps it can supply to your batteries is 30A. You'll likely never see that amount, unless you have sun conditions to be just perfectly right and have enough panels to support that. So if you were only getting 8A and usually see more than that, most likely it was due to the amount of sun (or lack thereof) you were getting at the moment.

Yes, this sounds good. If BMS charge protection doesn't trigger at 14.0V, then you can try a slightly higher voltage. So if you aren't getting BMS charge protection kicking in at 14.2V, then that's a very good sign that the cells in your battery are fairly well-balanced. Very very rarely can LiFePO4 batteries be charged fully to the 14.6V maximum and not trigger the BMS charge protection. It requires an extremely balanced battery to achieve that (took me a long time to understand that one!)


It means 90% capacity of the total battery capacity. Remember that these bluetooth-enabled BMS's give you an estimate of the SOC, but it's far more reliable the the (totally unreliable) reading that your Renogy Rover will give you.

Rant warning!
=========
Finally, I will say that I had a Renogy Rover 30A for about 4 years. It was a PITA to use. The user interface and the associated app(s) were so poorly designed that it came down to that I couldn't trust that the Rover wasn't damaging (or trying to) my expensive LiFePO4 battery. The settings wouldn't hold when I saved them...or at least it appeared they didn't hold (some people told me they were held even though the app showed me otherwise). I finally sold the damn thing and bought a Victron 100/30 to replace it. It's a night and day difference. Not only was the Victron a breeze to program, I TRUST that it isn't damaging my battery. I also see at least a 15% increase in solar production vs the Renogy, presumably due to it's faster MPPT tracking methods. Victron has lowered their price as well...in fact the Victron model is $27 cheaper!! (source: Renogy Rover 30 is $109+$30 Bluetooth dongle on Amazon, Victron has BT built-in).

I've since sold ALL my Renogy gear (except for a couple of panels) on ebay or craigslist. They were easy to sell because the average beginner solar consumer's perception of Renogy is a positive one. They do work, sort of, just poorly and inefficiently and are not a good bargain considering how much headache their products and customer service have given me.

Click to expand...

I just switched from lead acid to lithium this week. It was a 304 AH assemble it yourself kit from Docan. I'm slowly getting familiar with it. There are 87 parameters, many of which I have no clue about. It is now set at the default settings that came with the BMS.

The BMS at one point reported the batteries were at 97% capacity. Why didn't the BMS shut down or report an alarm? That is why I started changing the charger settings. I agree that the goal is to have the charge controller handle this, so an over voltage is never delivered to the battery.

When I got the 8 amps it was a bright sunny day. I repeated this test on another sunny day and got similar results. The floating started at about 70% of full charge and was around 80% by the end of the day. I will attach a graph and an excel file with the settings to show this.

I planned on operating between 10 to 90% SOC.

Thank you for all your help!

Frank Smith said:

14I just switched from lead acid to lithium this week. It was a 304 AH assemble it yourself kit from Docan. I'm slowly getting familiar with it. There are 87 parameters, many of which I have no clue about. It is now set at the default settings that came with the BMS.

Click to expand...

I have yet to build a DIY lithium battery, but have read enough that I feel confident to try it. But as for those 87 parameters, I don't know anything about. I'm sure if you post a new thread under the DIY battery subforum, you'd get some specific help on those.

Frank Smith said:

The BMS at one point reported the batteries were at 97% capacity. Why didn't the BMS shut down or report an alarm?

Click to expand...

Not sure how your BMS is setup, but why do you think the BMS should have shut down or sounded an alarm? 97% is not fully charged and most BMS's will not turn off the Charging MOSFET until at least one of the cells reaches 3.65V. Now even if you have set your target voltage of say 3.5V (14.0V for a 12v system, 56.0V for a 48V system ), the BMS will not shut down (aka "turn off Charging MOSFET" aka "charging protection") once it reaches that voltage. This is a good thing and what many of us aim for!! The charging protection feature of the BMS is ideally only triggered as a final fail-safe measure to protect the individual cells inside your lithium battery. Ideally, you don't want charging protection to be getting triggered every single day, because the MOSFET has a limited number of uses before it no longer works (how many? I have no idea, but probably hundreds at least.)

That is why I started changing the charger settings. I agree that the goal is to have the charge controller handle this, so an over voltage is never delivered to the battery.

Click to expand...

Yep, you got it, that's the goal here.

Frank Smith said:

When I got the 8 amps it was a bright sunny day. I repeated this test on another sunny day and got similar results. The floating started at about 70% of full charge and was around 80% by the end of the day. I will attach a graph and an excel file with the settings to show this.

Click to expand...

Thanks for that graph, that helps. I can see that the charging amps are about 8A around 7:45 and 15:45. This appears to be due to the nature of the sun rising and falling. Is this when you saw the 8A? If not, what other time(s) on this day did you see 8A and for long did you see that?

Also, what is the target voltage you have programmed in your charge controller? I see you have a 60A Renogy controller...this setting is labeled as "boost voltage" on the Renogys.

Dynoman said:

If the battery pack is Lifepo4 and using the USER settings with a Renogy Rover and the voltage is at 14.0 volts or more (Measured at the Battery) the battery should be in what's called the upper knee of the charge curve and approximately 97% or more charged.

As you suggest the Boost time is the setting to hold at Boost voltage before going to Float voltage and the only setting. It is the amount of time the Rover will hold the Boost Constant Voltage charge before going to the Float Constant Volt mode.

55 amps is a good charge rate in Boost, but should see the current decrease once boost starts. During Boost the charge current should decrease (tail) towards zero, but not reach zero. A Tail current of 4 or 5% when at the end of Boost is considered a nearly or fully charged battery. So at the end of the Boost Time the current in a 100ah battery should be around 4% 100ah x .04 = 4 amps. If at the end of the Boost Time the current has not decreased to around 4 or 5% increase the boost time until the current is around 4 or 5%. Note that I now charge to about 28.4 volts measured with Victron Smart Battery Monitor (24 volt system) for about 20 minutes and sometimes the boost current will be a low as 2 or 3 %.

The Float charge current to the battery should be near zero once the voltage has stabilized (13.5V) in float mode for 30 minutes or so. Around 30 minutes the charge to my battery bank is usually less than 1 amp and will continue to decrease. After and hour or 2 in float the current is usually bouncing + and - 0 amps.

Hope this helps...

Click to expand...

Are Boost and Float both constant voltage settings, with the setting for the boost higher than the float? Is that the only difference between them?

The Float charge current to the battery should be near zero once the voltage has stabilized (13.5V) in float mode for 30 minutes or so. Around 30 minutes the charge to my battery bank is usually less than 1 amp and will continue to decrease. After and hour or 2 in float the current is usually bouncing + and - 0 amps.

Click to expand...

That is the goal. When I had the lead acid batteries, it did this. If a big load like the microwave turned on, the charge current would increase to match it, holding the voltage fairly constant.

Thank you for all the posts about how to set this up. They helped a lot. I took my settings from them. I thought I had them exactly, but when I double checked, I had a couple of them wrong. Your controller seems to have a couple of settings that mine doesn't have. These are the settings I am trying today.

Here are the settings for today.

Frank Smith said:

Are Boost and Float both constant voltage settings, with the setting for the boost higher than the float? Is that the only difference between them?



That is the goal. When I had the lead acid batteries, it did this. If a big load like the microwave turned on, the charge current would increase to match it, holding the voltage fairly constant.

Thank you for all the posts about how to set this up. They helped a lot. I took my settings from them. I thought I had them exactly, but when I double checked, I had a couple of them wrong. Your controller seems to have a couple of settings that mine doesn't have. These are the settings I am trying today.

Here are the settings for today.

Click to expand...

"Are Boost and Float both constant voltage settings, with the setting for the boost higher than the float? Is that the only difference between them?"
Yes Boost (often called Absorb) and Float are both Constant Volt charge setting with Boost occurring first and after the Boost Charge Time is complete Float begins.

The Sequence is:
MPPT (also called Bulk) Constant Current Charging. In MPPT charge mode until Boost voltage reached.
Boost (also called Absorb) Constant Voltage Charging. In Boost charge mode until Boost Charge Time has elapsed.
Float Constant Voltage (Not really charging Battery, but holding battery at near full charge voltage while supplying loads power)

"Thank you for all the posts about how to set this up. They helped a lot. I took my settings from them. I thought I had them exactly, but when I double checked, I had a couple of them wrong. Your controller seems to have a couple of settings that mine doesn't have. These are the settings I am trying today."
A few questions to help me help you:
Is your Solar Charge Controller (SCC) the Renogy Rover 60 amp?
How is the Renogy SCC programmed? Using front panel or Blue Tooth (BT) module and App on phone?
Is the Battery 48 volt made from 16 304AH cells?
What BMS is connected to the Battery?

In general the settings look like a good place to start.