So I bought $1,492 LifePo4 Batteries for the RV, Now what?

Isaac-1

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Nov 4, 2021
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85
My motorhome turns 20 years old in a couple of weeks, so I thought it would be nice to buy it something special for its birthday. I have decided to upgrade the current battery system and solar charging system, budgeted $2,000 for this project, and so far I am on track to come in under budget at about $1,850 spent total.

The current setup was last updated in 2015, and consist of 4 100 watt solar panels wired in parallel, feeding a 35 amp PWM controller, which feeds a pair of 6V GC2 225AH golf cart batteries, which is connected to the various house loads including a Xantrex Prowatt SW 2000 pure sine inverter, for shore charging it has a Progressive Dynamics 9260 converter (60 amp).

So far I have bought a pair of 200AH ReBel LiFePo4 batteries, a Renogy 50 amp DC-DC charger with integrated MPPT solar controller, plus BT-2 module (both being delivered in the morning), along with various breakers, fuses, battery cables, etc. and one of these cheap $20 100 amp shunt meters https://smile.amazon.com/gp/product/B07W7XXKVF/ for initial testing.

I know the PD9260 is not an ideal charging source, but based on threads here regarding its charge profile it seems to be acceptable if the "charge wizard" is used to manually control full charging since boosts at 14.4VDC for 4 hours, then lowers to 13.6 for normal charging, and it floats at 13.2VDC in "storage" mode. (the converter goes into storage mode after it senses 30 hours without significant battery use, then boosts to 14.4V for 15 minutes once every 21 hours).

The batteries I bought were some discounted price mis-made 200AH batteries from ReBel batteries ReBel posted a video on these last month, to sum it up they tried ordering from a new supplier, and the batteries were not built fully to spec, most significantly the bluetooth switch is not waterproof, and they shipped with a 100A not a 150A smart BMS. At under $700 each before shipping I could not pass them up for 200AH Bluetooth enabled smart LiFePo4 batteries (same BMS as is in their 100AH batteries), they also have a total of 12 cells, (with 3X70AH cells in parallel, X4 in series, instead of the specced 4X single 200A cell)

For those of you that are still reading, what should I do with them when they get here?

I may not have time to install them in the RV for a few weeks with the holidays coming up, should I fully charge and load test them using the cheap shunt meter, the only handy charging source I have without pulling the PD9260 out of the RV is a 5a CV/CC bench supply, additional test equipment on hand is a Fluke 87V with i410 AC/DC clamp meter, and a HP / Agilent 54622A 2-channel 100 MHz Oscilloscope. I might also be able to rig up a higher amp power supply input to the Renogy DC-DC 50Amp MPPT controller, similar to what Will Prowse did in his review video of the Renogy unit.

thanks Ike
 
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Browneye

Dr. WattSon
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Nov 2, 2021
Messages
332
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Southern California
Subscribed...
I'm updating my 16yo winnebago. :)
I'm still using the pair of GC2's, added a 600w inverter and 430w of roof panels. My IOTAIQ4 has been perfect for the FLA's. I keep toying with getting a pair of battleborns or a big-battery owl. But I would have to spend a lot of money on upgraded chaarging processes - especially that IOTA would have to go. Can't modify it for charging lifepos.
 

williamsk913

Solar Enthusiast
Joined
Sep 27, 2019
Messages
75
My motorhome turns 20 years old in a couple of weeks, so I thought it would be nice to buy it something special for its birthday. I have decided to upgrade the current battery system and solar charging system, budgeted $2,000 for this project, and so far I am on track to come in under budget at about $1,850 spent total.

The current setup was last updated in 2015, and consist of 4 100 watt solar panels wired in parallel, feeding a 35 amp PWM controller, which feeds a pair of 6V GC2 225AH golf cart batteries, which is connected to the various house loads including a Xantrex Prowatt SW 2000 pure sine inverter, for shore charging it has a Progressive Dynamics 9260 converter (60 amp).

So far I have bought a pair of 200AH ReBel LiFePo4 batteries, a Renogy 50 amp DC-DC charger with integrated MPPT solar controller, plus BT-2 module (both being delivered in the morning), along with various breakers, fuses, battery cables, etc. and one of these cheap $20 100 amp shunt meters https://smile.amazon.com/gp/product/B07W7XXKVF/ for initial testing.

I know the PD9260 is not an ideal charging source, but based on threads here regarding its charge profile it seems to be acceptable if the "charge wizard" is used to manually control full charging since boosts at 14.4VDC for 4 hours, then lowers to 13.6 for normal charging, and it floats at 13.2VDC in "storage" mode. (the converter goes into storage mode after it senses 30 hours without significant battery use, then boosts to 14.4V for 15 minutes once every 21 hours).

The batteries I bought were some discounted price mis-made 200AH batteries from ReBel batteries ReBel posted a video on these last month, to sum it up they tried ordering from a new supplier, and the batteries were not built fully to spec, most significantly the bluetooth switch is not waterproof, and they shipped with a 100A not a 150A smart BMS. At under $700 each before shipping I could not pass them up for 200AH Bluetooth enabled smart LiFePo4 batteries (same BMS as is in their 100AH batteries), they also have a total of 12 cells, (with 3X70AH cells in parallel, X4 in series, instead of the specced 4X single 200A cell)

For those of you that are still reading, what should I do with them when they get here?

I may not have time to install them in the RV for a few weeks with the holidays coming up, should I fully charge and load test them using the cheap shunt meter, the only handy charging source I have without pulling the PD9260 out of the RV is a 5a CV/CC bench supply, additional test equipment on hand is a Fluke 87V with i410 AC/DC clamp meter, and a HP / Agilent 54622A 2-channel 100 MHz Oscilloscope. I might also be able to rig up a higher amp power supply input to the Renogy DC-DC 50Amp MPPT controller, similar to what Will Prowse did in his review video of the Renogy unit.

thanks Ike
Just out of curiosity, why did you order a 100amp shunt instead of 200amp plus? Would be nice to use all the continuous amps you can (assuming you will eventually install in RV).

If you want to test, maybe use your solar to charge as the other will be agonizingly slow. It might still take you a couple days depending on sunshine per battery. I'd be tempted to install in RV and use charger, you'll go that route anyway.
 

time2roll

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Joined
Mar 20, 2021
Messages
2,418
I know the PD9260 is not an ideal charging source, but based on threads here regarding its charge profile it seems to be acceptable if the "charge wizard" is used to manually control full charging since boosts at 14.4VDC for 4 hours, then lowers to 13.6 for normal charging, and it floats at 13.2VDC in "storage" mode. (the converter goes into storage mode after it senses 30 hours without significant battery use, then boosts to 14.4V for 15 minutes once every 21 hours).
Actually not as bad as you might think. I would leave the 9260 in place for this upgrade cycle.
 

williamsk913

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Joined
Sep 27, 2019
Messages
75
Actually not as bad as you might think. I would leave the 9260 in place for this upgrade cycle.
Yes, have the same charger and am leaving it. Some of the lithium charger hold the batteries at a high state of charge... Might be better than some 'lifepo4' charger options.
 

time2roll

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Mar 20, 2021
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I'm updating my 16yo winnebago. :)
I'm still using the pair of GC2's, added a 600w inverter and 430w of roof panels. My IOTAIQ4 has been perfect for the FLA's. I keep toying with getting a pair of battleborns or a big-battery owl. But I would have to spend a lot of money on upgraded chaarging processes - especially that IOTA would have to go. Can't modify it for charging lifepos.
If it has a separate IQ controller, IOTA has 9 different charge profiles.

IOTA IQ controllers

Have read some will users make adjustments internally but I don't know any details on that. If it is set for replacement there is no harm in poking around to find more info and give it a try.
 

Isaac-1

Solar Enthusiast
Joined
Nov 4, 2021
Messages
85
Just out of curiosity, why did you order a 100amp shunt instead of 200amp plus? Would be nice to use all the continuous amps you can (assuming you will eventually install in RV).

If you want to test, maybe use your solar to charge as the other will be agonizingly slow. It might still take you a couple days depending on sunshine per battery. I'd be tempted to install in RV and use charger, you'll go that route anyway.
Good question, because I don't plan to leave it installed in the motorhome, I will eventually get a better monitor for that if I decide I need one, instead this one will more to a shed that has 150 watt (?, I installed it about 7 years ago, so am going from memory) panel and a single group 31 12V lead acid battery which powers a wifi relay and a remote IP security camera, plus some LED lighting, typical power draw in the shed averages under 20 watts, often under 10 watts (depends on level of wifi activity).

As to recharging prior to install I have also bought a Renogy 50 amp DC-DC charger with MPPT which I will connect to a fixed output bench power supply and let it do the charge regulation similar to what Will Prowse did in his review video of this same unit. This should be able to give me 40-50 amps charging rate (BMS is rated at 50 amp charge rate, 100 amp discharge on 200 AH pack). With the Bluetooth monitor on the smart BMS and the Bluetooth monitor on the Renogy DC-DC MPPT charger there is not a lot of extra information that I would gain from a dedicated monitor. I just have to remember watt . amp draw from the battery BMS is double the display reading since the app only connects to 1 battery at a time.
 

Isaac-1

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Joined
Nov 4, 2021
Messages
85
Well so far so good, charged the batteries up to BMS cut off last night, then ran a discharge test today, ended up getting 6 hours and 26 minutes of run time down to 12.0V (when the inverter started squealing, as it was only getting 11.8V at the end of the wire), or 3.00v per cell (all were withing .03 at full discharge) at a constant 439 watt power draw according to the smart BMS (range of 438-440 W), amp hour metering on the cheap shunt meter got messed up, so I don't have a direct AH reading, but my math puts this at about 217.5 AH or so using 13.0 VDC as nominal voltage , not bad out of a battery pack advertised at 200AH.

Tomorrow I will try to duplicate this on the second battery
 

Tom C

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Joined
Sep 15, 2021
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6
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I'm updating my 16yo winnebago. :)
I'm still using the pair of GC2's, added a 600w inverter and 430w of roof panels. My IOTAIQ4 has been perfect for the FLA's. I keep toying with getting a pair of battleborns or a big-battery owl. But I would have to spend a lot of money on upgraded chaarging processes - especially that IOTA would have to go. Can't modify it for charging lifepos.
well...you might be able to modify the iota, but my results were not good. Seemed to work for a few days and appeared to kill the converter. I bought a 60 amp Progressive Dynamics that's made for LifePO. To be fair, I'm still undoing some other wiring quirks so maybe you'd have better luck. Only a $20 gamble. https://www.amazon.com/gp/product/B07FK4HFZN/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1
 

lexio

feel the balance 3.65
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Dec 12, 2020
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171
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the Netherlands
updated my 32 year old mb 100 last year it is nice to see a complete f1 weekend on a projector without shore power 2*272 ah
 

Browneye

Dr. WattSon
Joined
Nov 2, 2021
Messages
332
Location
Southern California
well...you might be able to modify the iota, but my results were not good. Seemed to work for a few days and appeared to kill the converter. I bought a 60 amp Progressive Dynamics that's made for LifePO. To be fair, I'm still undoing some other wiring quirks so maybe you'd have better luck. Only a $20 gamble. https://www.amazon.com/gp/product/B07FK4HFZN/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1
you mean try to remove the old IQ4 and install the new one? I don't even know what it might look like inside the case. For all we know there's a rj11 jack on the board.

Somebody was selling a 45A PD9145AL on ebay for $125. :)

I finally figured out why we have a 'converter/charger' in the first place - cuz you don't even need a battery then. :p

Now I'm trying to find a reliable built battery pack without spending $8/amp.
BigBattery and BatteryEvo - not sure. Ampere-Time...not sure. Battleborn...naw. DIY - uh no. LOL

On another note...the PV's went on the roof spendidly. :cool:

IMG_4080.HEIC
 
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