Battery bms stuck in protection mode - in parallel 2 total

[MickiF]

Hi, new here and novice! I just had my 2 agm’s replaced with chins bluetooth smart 12v 100ah. They have been great for a few weeks. I plugged into shore power for a few days, batteries remained full. When I unplugged, one battery remained in protection mode until the working one discharged to about 80%, then started discharging. I then drove to new destination, batteries 100% full. Now the other one is stuck in protection mode as the battery discharging, to run the rv is now down to 70%. A few questions… how do I get a battery, installed in horribly tight location, to drop the protection mode. Does this uneven discharge affect the life of batteries? Note: they have reached max charge prior to days of full charge without issue. I live in van so not easy to shut battery system down. Thanks for your time n hopefully this makes sense!

 

[JeromeS13]

So many questions... How do you have them wired? Gauge wires/length? How are you measuring the charge level? Do you have a shunt? How are you charging them?

 

[MickiF]

So many questions... How do you have them wired? Gauge wires/length? How are you measuring the charge level? Do you have a shunt? How are you charging them?

I used the existing wiring, it was a straight exchange from agm’s. my understanding is no shunt needed, it’s Bluetooth, I read an app on iPhone. I did tons of research, within my capabilities. My van is a travato, straight exchange is done all of the time on my year model n newer… I have no clue of wire gauge, I had someone install them for me. As I said they were working great until sitting at full charge for a few days… and thanks for your reply!

 

[Tomthumb62]

There are two “protection modes”. The BMS will tell you which one.

One mode is to stop discharging. The other mode is to stop charging. Sounds like it’s stopped charging one battery? And then the other?

My hunch is your shore charger isn’t programmed for lifepo4 batteries. It might also be set to “equalize” them, which is only for lead acid. If you try to put an equalize charge on a lifepo4, it will trigger the charging protection. Flooded lead acid requires a regular equalization charge cycle, which will charge at 15v or higher. Lifepo4 can’t handle more than 14.6v

What is the name and model of your shore charger? It might be possible to reprogram it for lifepo4.

 

[TacomaJoe]

Your iPhone app should tell you the battery status and why it is in protection mode. I would suspect either battery overvoltage or cell overvoltage. As they charge compare the readings with the protection values. You want to stop charging before it hits the protection level. Is your charger LiFePO4 compatible?

 

[MickiF]

i have a converter, is this what you mean by charger? Progressive Dynamics and I installed a boost plug for lLifo4 batteries. Batteries can be charged from solar, shore, generator.

I am almost clueless as to what the readings are on app. A few screenshots… and thanks!

 

[JeromeS13]

Something seems off with the wiring. The DMOS is still enabled, but the battery voltages aren't the same. If connected properly in parallel, they should be the same voltages..

 

[MickiF]

Again, battery ignorant novice here , what is DMOS? And they were charging and discharging balanced up until the time I plugged in for four days and had them sit at full charge. During the First few weeks of the install I was not plugged into shore power, charged from driving, solar and if running generator, during this time they both hit 100%, but both discharged about the same rate…

 

[Tomthumb62]

i have a converter, is this what you mean by charger? Progressive Dynamics and I installed a boost plug for lLifo4 batteries.

Yes that converter is also a charger. Look at the device and find out what the settings are set for. The default lithium settings may not be correct for your battery.

what is DMOS?

This stands for “Discharge MOSFET” which controls whether or not the battery can safely receive a charge.

 

[TacomaJoe]

DMOS is the Discharge MOS (switch). In protection mode the BMS turns off the CMOS (charge switch). Here's what I think is happening; your batteries are charging and sitting near full, a little more charge puts say battery A into protection mode, battery B will continue to take on some charge while A just sits there. When discharging battery B, having a higher charge, will start discharge first until it gets to the battery A level, then they track together.

Brings us to why did battery A protect itself? Your screenshots tell me a couple of clues. The app shows the voltage of the high cell and the low cell. They should be pretty close in a balanced battery. Yours were 105mV apart. I also note the BALANCE function is OFF. Not sure if that is displaying the current status or a switch function. Need to drill into some settings on your BMS.

 

[MickiF]

DMOS is the Discharge MOS (switch). In protection mode the BMS turns off the CMOS (charge switch). Here's what I think is happening; your batteries are charging and sitting near full, a little more charge puts say battery A into protection mode, battery B will continue to take on some charge while A just sits there. When discharging battery B, having a higher charge, will start discharge first until it gets to the battery A level, then they track together.

Brings us to why did battery A protect itself? Your screenshots tell me a couple of clues. The app shows the voltage of the high cell and the low cell. They should be pretty close in a balanced battery. Yours were 105mV apart. I also note the BALANCE function is OFF. Not sure if that is displaying the current status or a switch function. Need to drill into some settings on your BMS.

Appreciate your looking. There is the ability to manually turn on the balance function, which I tried, it then turns off. Question, maybe I need to turn on both battery’s balance at once? screenshot of options… in the recent past, since only a few weeks installed, the balance came on randomly, but like I said, everything was peachy keen til it got stuck!
image with all 3 on is the battery charging, other is stuck in protection mode… and really thank you! Again, 1000’s have done a simple agm’s to lithium swap with renogy, battle born, even a few other chinese brands with rigs like mine, and have had no issues…

 

[mikefitz]

Your charge voltage is too high. This puts one of the batteries Into protection mode.
Until this battery falls below the reconnect voltage, your other battery supplies the load.
Chins batteries will be supplied with cells that are not matched, thus when nearing full charge one cell will trigger cell overvolts and shut down the battery. The higher the charge voltage is to 14.6 volts, the most likely this will occur. A charge voltage of 14.4 or even lower to 13.8 volts may be needed. Providing balance is enabled in the BMS , after come time the batteries will become better balanced.

I suspect your shore power charger is set to a charge voltage that is too high, and/ or, the protection levels and balance settings are incorrect inthe BMS. I think the lithium charge voltage for the Progressive Dynamics is 14.6 volts.
Since you had someone else carry out the instalation they may have changed BMS settings in the battery, and set up the charge voltage on the shore power charger to a less than ideal value.
I assume the situation is not compromising systems in the van and if you did not have communication to the batteries, you would be quite happy.
Unlike lead acid , lithium batteries are not required to be always fully charge, or kept in a fully charged state, in fact this reduces service life.
Info on a Chins battery issue,

Chins Smart 12.8V 100Ah drop in

I recently ordered the Chins Smart 12.8V 100Ah drop-in battery from Amazon for evaluation. This is the version with a heating pad to warm the battery if less than 0 C and Bluetooth BMS interface, and paired with the EE-BMS app. According to the app, it had a tested 105.5 Ah tested capacity and...

diysolarforum.com

Mike

 

[MickiF]

Thanks, I think! From what I’m understanding I am only operating on one battery though correct? The guy that installed them did nothing but install the batteries. He didn’t know enough about anything to change any settings, there were no settings to change. Once I got the batteries changed out, I put the doggle in the converter aux plug to keep it at a higher charge for lithium. I changed my Zamp controller to life4o.

Yes I’m a little confused… I Have rdad lithium’s will last longer if they’re not at a full charge, more like between 30 and 70%, but when one plugs into shore power for three or four days can’t help but have but have them full charge , and still be able to run all the systems in the van. I have spoken with the gentleman who does a lot of installs on Travato’s, but he uses battle born’s so he’s never had this problem… How do I get it out of protection mode? I will read the other thread. Thanks again. Why can’t things be easy… Just sometimes!

 

[MickiF]

Your charge voltage is too high. This puts one of the batteries Into protection mode.
Until this battery falls below the reconnect voltage, your other battery supplies the load.
Chins batteries will be supplied with cells that are not matched, thus when nearing full charge one cell will trigger cell overvolts and shut down the battery. The higher the charge voltage is to 14.6 volts, the most likely this will occur. A charge voltage of 14.4 or even lower to 13.8 volts may be needed. Providing balance is enabled in the BMS , after come time the batteries will become better balanced.

I suspect your shore power charger is set to a charge voltage that is too high, and/ or, the protection levels and balance settings are incorrect inthe BMS. I think the lithium charge voltage for the Progressive Dynamics is 14.6 volts.
Since you had someone else carry out the instalation they may have changed BMS settings in the battery, and set up the charge voltage on the shore power charger to a less than ideal value.
I assume the situation is not compromising systems in the van and if you did not have communication to the batteries, you would be quite happy.
Unlike lead acid , lithium batteries are not required to be always fully charge, or kept in a fully charged state, in fact this reduces service life.
Info on a Chins battery issue,

Chins Smart 12.8V 100Ah drop in

I recently ordered the Chins Smart 12.8V 100Ah drop-in battery from Amazon for evaluation. This is the version with a heating pad to warm the battery if less than 0 C and Bluetooth BMS interface, and paired with the EE-BMS app. According to the app, it had a tested 105.5 Ah tested capacity and...

diysolarforum.com

Mike

Sorry, I replied to you below.

 

[MickiF]

Your charge voltage is too high. This puts one of the batteries Into protection mode.
Until this battery falls below the reconnect voltage, your other battery supplies the load.
Chins batteries will be supplied with cells that are not matched, thus when nearing full charge one cell will trigger cell overvolts and shut down the battery. The higher the charge voltage is to 14.6 volts, the most likely this will occur. A charge voltage of 14.4 or even lower to 13.8 volts may be needed. Providing balance is enabled in the BMS , after come time the batteries will become better balanced.

I suspect your shore power charger is set to a charge voltage that is too high, and/ or, the protection levels and balance settings are incorrect inthe BMS. I think the lithium charge voltage for the Progressive Dynamics is 14.6 volts.
Since you had someone else carry out the instalation they may have changed BMS settings in the battery, and set up the charge voltage on the shore power charger to a less than ideal value.
I assume the situation is not compromising systems in the van and if you did not have communication to the batteries, you would be quite happy.
Unlike lead acid , lithium batteries are not required to be always fully charge, or kept in a fully charged state, in fact this reduces service life.
Info on a Chins battery issue,

Chins Smart 12.8V 100Ah drop in

I recently ordered the Chins Smart 12.8V 100Ah drop-in battery from Amazon for evaluation. This is the version with a heating pad to warm the battery if less than 0 C and Bluetooth BMS interface, and paired with the EE-BMS app. According to the app, it had a tested 105.5 Ah tested capacity and...

diysolarforum.com

Mike

So quick question, if it’s better not to do a full charge, then maybe I should just charge a 13.6 as the default converter would do if I removed the dongle from the auxiliary port… Not something I want to try often on too much since it’s hidden beneath Cabinets and I can barely barely reach took me three tries to get it in to begin with

 

[HRTKD]

There is a lot of dissatisfaction with the traditional converter. They charge too slow, they charge too high, etc. Any converter that wants to charge to 14.6 volts every time is not one that I want in my system. My components are programmable, so they charge to exactly what I think will help my LiFePO4 battery bank last a long time. That's 14.4 volts when the camper is active and 14.2 volts when it's in storage. Most of the time it's loafing along at 13.5 to 13.6 volts but close to zero amps. I don't think I've EVER had an overcharge exception on either of my LiFePO4 batteries.

 

[MickiF]

There is a lot of dissatisfaction with the traditional converter. They charge too slow, they charge too high, etc. Any converter that wants to charge to 14.6 volts every time is not one that I want in my system. My components are programmable, so they charge to exactly what I think will help my LiFePO4 battery bank last a long time. That's 14.4 volts when the camper is active and 14.2 volts when it's in storage. Most of the time it's loafing along at 13.5 to 13.6 volts but close to zero amps. I don't think I've EVER had an overcharge exception on either of my LiFePO4 batteries.

And are you using? and thank you for the information!

 

[HRTKD]

And are you using? and thank you for the information!

When I put in LiFePO4 batteries I started with an IOTA Engineering DLS-55 with the IQ/4-LiFePO4 module. It did OK, mainly because I'm rarely on shore power and even less rarely have to run my on-board generator. I switched to that model from a DLS-45 that only charged lead acid batteries. For those times that I would be on shore power I wanted a safe charge for the LiFePO4 batteries. It was safe, but it wasn't ideal for those couple of times when I did need a charge from the generator. It just didn't seem to ever want to charge close to its rating.

When I installed my Victron Multiplus 12/3000 inverter/charger I removed the converter altogether and now use the Multiplus to charge the batteries. A single combined unit is easier to deal with.

 

[Tomthumb62]

if it’s better not to do a full charge, then maybe I should just charge a 13.6

Keep in mind that many retail lifepo4 batteries require hitting 14.4-14.6V to trigger the self balancing functions. Without this, your battery can get out of balance over time, which can affect capacity and other things.

Most of the people claiming they never charge more than 13.6-13.8v are using DIY lifepo4 battery packs that have beefy active balancers installed. Unless you want to cut open your battery to install an active balancer, you’ll need to rely upon the built in passive balancing functions.

What I do is use solar to charge to 14.0v and when shore power is available (once a week or so), use my Victron AC 30A charger to charge up to 14.4v

 

[MickiF]

When I put in LiFePO4 batteries I started with an IOTA Engineering DLS-55 with the IQ/4-LiFePO4 module. It did OK, mainly because I'm rarely on shore power and even less rarely have to run my on-board generator. I switched to that model from a DLS-45 that only charged lead acid batteries. For those times that I would be on shore power I wanted a safe charge for the LiFePO4 batteries. It was safe, but it wasn't ideal for those couple of times when I did need a charge from the generator. It just didn't seem to ever want to charge close to its rating.

When I installed my Victron Multiplus 12/3000 inverter/charger I removed the converter altogether and now use the Multiplus to charge the batteries. A single combined unit is easier to deal with.

Thank you and what that first sentence was suppose to ask ?, what batteries are you using…