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Chins Bluetooth BMS State of Charge? - in parallel with non-Bluetooth battery

eXodus

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Jul 27, 2020
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Hello,

I currently have one 24V 200AH Chins battery:
1665308256799.png

I want to buy a second one - and got told by the Chins seller that the next version will have a Bluetooth BMS with app and state of charge.

So I wanted to put those batteries in parallel, how would it display the state of charge? Is it based on the voltage? can I assume that when I look at the state of charge from a pair or or more in parallel- (with 0/2 cable) that they are about similar? Battery cells are the same - just different BMS.

Thanks!
 
I have four Chins 100 Ah 12V batteries in parallel, one of which has the BT BMS. The whole bank is monitored by a Victron BMV-712 battery monitor. While the parallel wiring is not the ideal, I think the BT BMS overestimates the state of charge, compared to the BMV-712 tally, but I have not tried to verify that. It does not appear to be based on battery voltage, and it should not be.
 
I think the BT BMS overestimates the state of charge, compared to the BMV-712 tally,
How much is your guess it overestimates? 10% 20%?

Currently I use my Growatt Inverters SOC - and that is horrible. It shows 100% for about 4 kWh of discharge (from a 5kWh battery) and then drops like a stone for the last one kWh. So pretty useless.

I just ordered the second Chins battery got it to a good price, We shall see how good their BMS is.
 
How much is your guess it overestimates? 10% 20%?

Currently I use my Growatt Inverters SOC - and that is horrible. It shows 100% for about 4 kWh of discharge (from a 5kWh battery) and then drops like a stone for the last one kWh. So pretty useless.

I just ordered the second Chins battery got it to a good price, We shall see how good their BMS is.
Less than 10%
 
Less than 10%
10 percent is perfectly fine. That's within a normal error range.
I never discharge my batteries all the way for longevity.

Currently I basically have a empty fuel tank idiot light. Without a gauge. I don't know the SOC until almost empty ;)
 
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