Skip to main content

HX-JH-004 4S 12V LiFePO4 balancer board test

A typical LFP or LiFePO4 cell has 3.2V nominal voltage which means that if you connect 4 LFP cells in series you’ll have a 12.8V battery pack. The charge end voltage for a 4S pack would be 4×3.65V= 14.6V but as you know battery packs need to be balanced to serve for a long time, especially if the cells have different internal resistance.
HX-JH-004 4S 12V LiFePO4 balancer board test review | Thunderheart Reviews

HX-JH-004 is a balancer board for a 4S LFP battery pack which should not be confused with BMS – the latter also protects the battery pack from overcharging, overdischarging and going overcurrent. HX-JH-004 only does the balancing.
HX-JH-004 4S 12V LiFePO4 balancer board test review | Thunderheart Reviews

Specifications of HX-JH-004 4S LFP balancer board
Dimensions (LWH): 26×20.5×2.4mm
Balancing current for each cell: 58mA
Balancing voltage for each cell: 3.60V (14.4V for the 4S LiFePO4 battery pack)

So when a cell’s voltage goes above 3.60V the balancer shoud start discharging until it reaches the 3.60V limit.

Let’s take a closer look at the components on the PCB.
HX-JH-004 4S 12V LiFePO4 balancer board test review | Thunderheart Reviews

There are 4 channels with identical set of elements the biggest one of which is the 62Ω resistor (marked 620) which defines the 58mA balancing (discharging) current.
HX-JH-004 4S 12V LiFePO4 balancer board test review | Thunderheart Reviews

Next comes a H&M Semi HM2302A (datasheet) n-channel power MOSFET in SOT-23-3L package with A2SHB marking, a Hycon HY2212-BB3A (datasheet) battery charge balance IC in SOT-23-6 package (marked AB3A M60J), an SMD capacitor and a 100Ω SMD resistor (marked 101).


Wiring the board to a 4S battery pack

For those who are going to build a pack for the first time here is the wiring scheme:
HX-JH-004 4S 12V LiFePO4 balancer board test review | Thunderheart Reviews

I’ve used 0.5mm copper wire for wiring.
HX-JH-004 4S 12V LiFePO4 balancer board test review | Thunderheart Reviews

The PCB with soldered wires looked like this:
HX-JH-004 4S 12V LiFePO4 balancer board test review | Thunderheart Reviews

I used a holder for 4×18650-size cells and I intentionally used different cells with different internal resistance to complicate the job for the balancer.
HX-JH-004 4S 12V LiFePO4 balancer board test review | Thunderheart Reviews


Testing

The measurements showed that the balancing current was 58-59mA which is exactly what the specs tell. I’ve repeated the test 3 times. Between charging and balancing a 1-hour pause was left to have stable voltages of the cells.

Ch – number of channel of the balancer
Cell – number of cell
Before – cell voltage before balancing
After – cell voltage after balancing
Δ – the difference with 3.6V for a cell and the difference with 14.4V for the pack

ROUND 1
Ch
Cell
Before
After
Δ
1
1
3.768
3.600
0.000
2
2
3.625
3.596
0.004
3
3
3.725
3.595
0.005
4
4
3.707
3.584
0.016
Pack V after balancing: 14.375
0.025
.
ROUND 2
Ch
Cell
Before
After
Δ
1
1
3.697
3.600
0.000
2
2
3.685
3.595
0.005
3
3
3.663
3.596
0.004
4
4
3.683
3.583
0.017
Pack V after balancing: 14.374
0.026

In round 3 I’ve swapped the 1st and 4th cells to exclude the impact of a cell-channel combination.
ROUND 3
Ch
Cell
Before
After
Δ
1
4
3.691
3.598
0.002
2
2
3.692
3.599
0.001
3
3
3.678
3.595
0.005
4
1
3.694
3.587
0.013
Pack V after balancing: 14.379
0.021

In the first two rounds the cell on the first channel was discharged down to 3.600V which looks pretty nice. The next two channels were below 3.6V by 0.004-0.005V which is a miserable delta. Only the 4th channel was below 3.6V by 0.016-0.017V which is not as low as the other channels but still a good result.

The 3rd round showed that the results don’t rely on cell-channel combination because the first channel with the cell №4 again showed almost no difference with 3.6V and the 4th channel’s delta was again higher than 0.01V – 0.013V to be exact.


Upgrade

During balancing the 62Ω resistors heat up the board up to 60°C. To cool it down I took a couple of 9×9×5mm heatsinks and cut the ribs to 2.1mm
HX-JH-004 4S 12V LiFePO4 balancer board test review | Thunderheart Reviews

I attached them together by putting a sticky insulation tape on long sides. It’s very important to use insulation to avoid contact between the heatsink and resistors.
HX-JH-004 4S 12V LiFePO4 balancer board test review | Thunderheart Reviews

Then I applied some thin layer of thermal conductive glue to resistors.
HX-JH-004 4S 12V LiFePO4 balancer board test review | Thunderheart Reviews

And accurately put the heatsink on to the resistors and left to cure for several hours.
HX-JH-004 4S 12V LiFePO4 balancer board test review | Thunderheart Reviews

This upgrade helped to lower the temperature by 8-10°C.


Verdict

So, this balancer is not bad at all. The first 3 channels’ accuracy is between 0-0.005V and only the last channel showed 0.013-0.017V difference with 3.6V target voltage. The balancing current is 58-59mA which is also quite accurate. The high operating temperature is something I didn’t like and put an aluminium heatsink but even without that additional cooling the board will work fine. I took it for $1.5 which is not a too high price for such a performer.

Here is the video version of this review:
HX-JH-004 4S 12V LiFePO4 balancer board test review | Thunderheart Reviews

Check out my YouTube channel for batteries, chargers and other stuff reviews.

Popular posts

Samsung 50E capacity test - 5000mAh or not?

Samsung INR21700-50E is a 21700 size cell which is being sold as 5000mAh one while in its official datasheet the capacity is mentioned as "Min. 4900mAh". I've tested it to find out it's real capacity. The battery was bought from my reliable supplier ( Queen Battery ) and tested  with  ZKETECH EBC-A20  and a self-made battery holder. It's a PC-connected battery tester supporting 4-wire measuring and discharging at up to 20A. I've used version 3.0 of my battery holder based on 0.5mm thick pure copper terminals I've followed all the prescriptions of the  IEC61960-2003  standard concerning battery's capacity measurement. Before each discharging cycle each battery was charged at standard charge current mentioned in its datasheet to charge end voltage. Before each discharging or charging i've held a 1-1.5hrs pause. The environment temperature was 23.0-24.5°C. To be sure in results i've done each test minimum twice (usually 3-4 times). S

3500mAh 18650 Li-ion cells' discharge capacity test (Sanyo NCR18650GA vs Panasonic NCR18650GA vs LG MJ1 vs Samsung INR18650-35E)

Hi guys! I’ve got four 3500mAh batteries from top manufacturers. I’ve tested and compared them. I think it’s interesting not only for me, but also for you, the guy who is reading this:) The cells were bought from Queen Battery , a Chinese supplier of genuine batteries, who specializes mainly on EV and eBike market. Queen Battery has a branch in Europe, but they also work with customers from Americas, Russia, etc… As always, I've tested with ZKETECH EBC-A20 and a self-made battery holder. It's a PC-connected battery tester supporting 4-wire measuring and discharging at up to 20A. I've followed all the prescriptions of the IEC61960-2003 standard concerning battery's capacity measurement. Before each discharging cycle each battery was charged at standard current mentioned in its datasheet to 4.2V (cut-off at 0.1A, which is the lowest supported by EBC-A20). Before each discharging or charging i've held a 1-1.5hrs pause. The environment temperature was 20-

Sony VTC6 - a 3000mAh/30A monster in 18650 size

Sony US18650VTC6 (or just VTC6) is a high drain 18650 size Li-ion cell which supports discharge rate up to 15A if no temperature control is used and up to 30A with 80°C temperature cut. The battery was bought from my reliable supplier ( Queen Battery ) and tested  with  ZKETECH EBC-A20  and a self-made battery holder. It's a PC-connected battery tester supporting 4-wire measuring and discharging at up to 20A. I've used version 3.0 of my battery holder based on 0.5mm thick pure copper terminals I've  all the prescriptions of the  IEC61960-2003  standard concerning battery's capacity measurement. Before each discharging cycle each battery was charged at standard charge current mentioned in its datasheet to charge end voltage. Before each discharging or charging i've held a 1-1.5hrs pause. The environment temperature was 23.0-24.5°C. To be sure in results i've done each test  minimum twice  (usually 3-4 times). Sony US18650VTC6 The  c ell is  marked a

Li-ion 21700: LG M50 5000mAh vs Samsung 48G 4800mAh discharge capacity test

Hi guys! I've tested two high capacity 21700 cells - LG M50 (5000mAh) and Samsung 48G (4800mAh). The latter i had already tested before and the re-testing of another cell showed almost no difference with previous test results. The M50 is a new cell which is being sold as 10A one, but in its datasheet the maximum discharge current is mentioned as 7.28A. Nevertheless i've also discharged it at 10A to look at it's behavior. The cells i've bought from Queen Battery . As always, I've tested with ZKETECH EBC-A20 and a self-made battery holder. It's a PC-connected battery tester supporting 4-wire measuring and discharging at up to 20A. I've used the v2.5 of my battery holder I've followed all the prescriptions of the IEC61960-2003 standard concerning battery's capacity measurement. Before each discharging cycle each battery was charged at standard current mentioned in its datasheet to charge end voltage (4.2V) (cut-off at 0.1A, which is th

Samsung 40T - high drain 21700 Li-ion battery's capacity test

Hi guys! I've tested the Samsung INR21700-40T (35A) at up to 20A discharge (limited by my equipment). The battery was bought from my reliable supplier ( Queen Battery ) and tested  with  ZKETECH EBC-A20  and a self-made battery holder. It's a PC-connected battery tester supporting 4-wire measuring and discharging at up to 20A. I've used version 3.0 of my battery holder based on 0.5mm thick pure copper terminals I've followed all the prescriptions of the  IEC61960-2003  standard concerning battery's capacity measurement. Before each discharging cycle each battery was charged at standard charge current mentioned in its datasheet to charge end voltage. Before each discharging or charging i've held a 1-1.5hrs pause. The environment temperature was 23.5-24.5°C. To be sure in results i've done each test minimum twice (usually 3-4 times). Samsung INR21700-40T The c ell is marked as  INR21700-40T SAMSUNG SDI 2I15 which mean s that the production d

LG M36 vs Samsung 36G capacity test - 3600mAh or just marketing?

The first 3600mAh Li-ion battery in 18650 format appeared 4-5 years ago. It was Panasonic NCR18650G. But it disappeared from the market very quickly and since then there was no 3600mAh cell you could buy (except fakes on eBay). Now two of top manufacturers, LG and Samsung, offer their cells, which are being sold as 3600mAh ones - LG INR18650 M36T and Samsung INR18650-36G . Let's check if they are real 3600mAh ones. As always the tests were done using  ZKETECH EBC-A20 , which supports up to 20A discharge, 4-wire measurement and is PC-connected. I've upgraded my battery holder to the version 3.0 This time i've used thicker (0.5mm) pure copper strips (9mm and 11.5mm wide). The parts which contact with the cell are rised a bit to provide reliable connection when a cell with deep placed contact(s) is held. I've followed all the prescriptions of the  IEC61960-2003  standard concerning battery's capacity measurement. Before each discharging cycle each bat