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

[eXodus]

Hello,

I currently have one 24V 200AH Chins battery:

12V/24V LiFePO4 Series

Product Series Introduction Regular model battery with built-in BMS, BMS has the following functions: overcharge protection, overdischarge protection, overcurrent protection, temperature protection, short circuit protection.

chins.shopping

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!

 

[electrongeek]

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.

 

[eXodus]

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.

 

[electrongeek]

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%

 

[eXodus]

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