If you connect several cells in series, you definitely want a BMS. If not for optimisation purposes then for sure for safety and peace of mind. A BMS controls and monitors your whole battery on cell level niveau, disconnects the whole battery in case of over or under voltage and prolongs the life of your precious battery. An active balancer just balances your batteries, shuffles energy from one cell with higher voltage to one with lower voltage. Over time, your pack will be perfectly balanced.
Here is a selection of good Battery Management Systems and Balancer to use for your LiFePo4 battery cells.
JK BMS with integrated active Balancer
This is the BMS we have all waited for. It’s the Jack of all trades, the ultimate BMS AND balancer combined in one device, controlled with one app.
The video with the first setup, comprehensive review and practice test is here now! Wow, I’m impressed with this BMS and it has my full recommendation.
AliExpress product link: 8S ~ 24S 1A/2A Active Balance current 200A continues current (350A max).
DC Booster connection:
The BMS can be used with a 4s/12V battery as well with the help of a DC booster (AliExpress product link for the 12V/24V booster)
See the video for the setup here.
JK BMS manual including wiring diagram for booster. (PDF, 1MB)
8s LiFePO4 SMART BMS 200A with 2A Active Balancer
This BMS is very similar to the JK BMS above and made for 24V systems. It does not need a booster or power supply as it runs directly from the battery. I have not tested this BMS yet but it uses the same great Bluetooth app and it’s an alternative for 24V systems (8s LiFePO4 battery packs)
AliExpress product link (8s LiFePO4 Smart BMS, 200A, 2A active balancing)
QUCC has got a new version of the Relay-BMS. I must say it’s not as pretty as the old version I have but it’s not a beauty contest, so… yeah The Relay is back!
For both Li-ion and LiFePO4 cells from 13s-20s configuration. It still has 200A permanent and 600W peak current.
Bluetooth is included and you can now also program the sleep time when the relay falls off again (as per manufacturer information, mine does not have this function).
QUCC has a very good customer service (they replaced my faulty BMS in no time) and replies to enquires on AliExpress within minutes.
Common port LiFePO4 and Li-ion Smart BMS with Bluetooth function and app support:
200A with relay: AliExpress product link
150A. 4-8S: AliExpress product link
80A-120A 13-15S: AliExpress product link
30A-100A 16-20S: AliExpress product link
Spare relay 500A 12V/24V: AliExpress product link
Separate port BMS with 2 relays and display, Bluetooth and app support, 300A
AliExpress product link for 3s-8s Li-ion and LiFePO4
AliExpress product link for 12s-16s Li-ion and LiFePO4
Link to newest Xiao Xiang App for QUCC and other BMS’s.
JBD Smart Bms 12V 4S Lifepo4 100A
I tested this BMS recently and found a major problem with the temperature disconnect function (a safety feature!). It does not disconnect load/charger if the current is under the threshold. You can keep charging or discharging the battery in cold/hot weather and damaging your battery.
With such a basic safety feature not working, I cannot recommend the BMS at this stage.
Watch the full video review here.
Daly Smart BMS
Very good quality BMS with a lot of features (access through a PC only though). I’m still a bit disappointed with Daly using such a weird method to balance the cells. Passive balancing is outdated, old-school. The JK BMS above is far superior with its app, features and balance method.
See the full video review here.
And, we found out how the Daly BMS works and balances.
Watch the video here.
3s – 24s Li-ion and LiFepO4 BMS from 80A up to 500A:
AliExpress product link
HANKZOR Active Equalizer Balancer
I have used these balancers for testing and they are working great. Even with the big capacity cells, they don’t have a problem as they can transfer up to 5A from one cell to another.
I’ve done some testing with these balancers and show this in the video here and here. They really pushed close to 5A across the cells even at lower voltage difference of only 0.7V.
You can order them from 3S up to 21S and they work with all sort of batteries together: Li-ion, LFP and LTO.
I was able to squeeze out a coupon code from the Hankzor Store on AliExpress for you. Use the code WYH8B9UBPQ7W at checkout for some extra discount (min spend is $15)
AliExpress product link 3s-17s active balancer, 5A balance current
NEEY – 4A Active Smart Balancer with Bluetooth
The NEEY active smart balancer is now working as expected. Well, almost at least. You need to know that it reacts to the average cell voltage and not to the maximum cell voltage as all other BMS’ do. This is per design and still works fine, you just need to know.
Please watch the final test and review video here.
This active balancer can be programmed via Bluetooth app to your needs. Deviation, sleep voltage, balance current… It balances with 4A at any point of time, regardless the voltage difference between the cells. The active balancer can work with all batteries from 2s to 24s batteries configuration.
Watch this video here for a first impression and review.
AliExpress product link
App download (NEEY Github website)
All links on this page are affiliate links to support the channel. I’m getting paid a small commission if you order products or services through these links. This does not make the products or services more expensive for you.