ajw22
Member
- Joined
- Nov 16, 2018
- Messages
- 733
A Batrium system was a little too expensive for me, so I decided to use a cheap-ish (42USD)Chinese BMS for my Lithium Ion 1865014S92P / 160Ahbattery.I've done 3 charge-discharge cycles, and so far I'm very happy with it.
This is it:
https://www.aliexpress.com/item/14S...402.html?spm=a2g0s.9042311.0.0.27424c4d8tRQhp
It has all the basic safety features such asto cut off discharge when:
* any cell goes below the safety voltage
* combined battery voltage below safety voltage
* over current
* over / undertemperature
and also cut off charge when:
* any cell goes above the safety voltage
* combined voltage above
* over current
* over / under temperature
and a lot more features listed in the link.
The best part is that all the voltage / current /temperature trigger values can be adjusted using the smartphone app (bluetooth connection) or a PC app (USB). A bit stupid that some settings can only be modified using the PC app. The voltage/current sensors can also be calibrated, which fixed my BMS Amps reading being off byalmost 2x.
My main concern was the balancing function, as it can only drain at 50mA. Many cheap BMS start balancing only when a cell has reached 4.2V, butthis one has many option on when it should balance. I'm very happy with my settings of:
balancewhen{ cell voltage >3.8V } and { voltage diff of 0.02V or more} and { battery is being charged}
So far, this has been plenty to keep by packs balanced. If it should not suffice, I can change it to balance 24/7 instead of only when being charged.
It's also reasonably easy to do some basic troubleshooting of the packs. The packs were initially all in the 4.08V~4.16V range.After my first discharge, the BMS reported thatpacks #7 and #12had much lower voltages:
Turned out that the fuse wire on4 cells on pack #7 were not properly soldered, and pack #12 had 2 cells with the same problem. After fixing those issues and 2 cycles later (ca 20h of charging/balancing in total)all the packs were top balanced to within 0.02V difference. On discharge:
pack #11 is a little weak, but still within my "good enough" range.
I'm quite happy with this BMS, and I've ordered 3 more to use in my next batteries.
The only thing I'm not too happy about is the limited range of the bluetooth requiring me to be basically in the room to check the status. Wifi remote monitoring would have been awesome.
This is it:
https://www.aliexpress.com/item/14S...402.html?spm=a2g0s.9042311.0.0.27424c4d8tRQhp
It has all the basic safety features such asto cut off discharge when:
* any cell goes below the safety voltage
* combined battery voltage below safety voltage
* over current
* over / undertemperature
and also cut off charge when:
* any cell goes above the safety voltage
* combined voltage above
* over current
* over / under temperature
and a lot more features listed in the link.
The best part is that all the voltage / current /temperature trigger values can be adjusted using the smartphone app (bluetooth connection) or a PC app (USB). A bit stupid that some settings can only be modified using the PC app. The voltage/current sensors can also be calibrated, which fixed my BMS Amps reading being off byalmost 2x.
My main concern was the balancing function, as it can only drain at 50mA. Many cheap BMS start balancing only when a cell has reached 4.2V, butthis one has many option on when it should balance. I'm very happy with my settings of:
balancewhen{ cell voltage >3.8V } and { voltage diff of 0.02V or more} and { battery is being charged}
So far, this has been plenty to keep by packs balanced. If it should not suffice, I can change it to balance 24/7 instead of only when being charged.
It's also reasonably easy to do some basic troubleshooting of the packs. The packs were initially all in the 4.08V~4.16V range.After my first discharge, the BMS reported thatpacks #7 and #12had much lower voltages:
Turned out that the fuse wire on4 cells on pack #7 were not properly soldered, and pack #12 had 2 cells with the same problem. After fixing those issues and 2 cycles later (ca 20h of charging/balancing in total)all the packs were top balanced to within 0.02V difference. On discharge:
pack #11 is a little weak, but still within my "good enough" range.
I'm quite happy with this BMS, and I've ordered 3 more to use in my next batteries.
The only thing I'm not too happy about is the limited range of the bluetooth requiring me to be basically in the room to check the status. Wifi remote monitoring would have been awesome.