boboxx
New Member
Who here has a 5a active balancer? Does the led labelled "work" go out once it reached the same voltage or if the cells go bellow 2.9v?
5A Active Balancer
- Thread starter boboxx
- Start date
boboxx
New Member
boboxx
New Member
Mine is definitely working but it's not turning off!
boboxx
New Member
Yes I used the multimeter, the cell where not off by much and it was pulling 1.4a.
boboxx
New Member
None, I have just bee cycling the cells so far. I will be doing a bottom balance
boboxx
New Member
injunear_derf
New Member
An Active balancer that looks just like that one from "electronic-mail" on Ebay fried my 24V 50Ahr battery. Is costing me $561 to repair. I'm 90% sure it was the balancer as cell voltages went from 0.01-0.7V to 1.0-1.3V after I disconnected it. I don't recommend this balancer at all.
Solarfun4jim
Solar seduced :-)
I didnt think these 5A balancers work, unless you had really bad cells. It is my understanding, that you only get 1A balancing if the cells differ by 100mV. Lets face it, most of us are having a fit 
if our cells drift past 20mV in difference. To get the full 5A active, your cells need to be out by 1V and if thats the case, i might think the system had bigger issues. Great for maximising capacity out of heavily used second hand packs, but i'd be doubtful if you would even see them working on a 'new' top balanced pack.
I'm no expert, but that's my reading of them...most likely i have it wrong !!!
if our cells drift past 20mV in difference. To get the full 5A active, your cells need to be out by 1V and if thats the case, i might think the system had bigger issues. Great for maximising capacity out of heavily used second hand packs, but i'd be doubtful if you would even see them working on a 'new' top balanced pack.I'm no expert, but that's my reading of them...most likely i have it wrong !!!
injunear_derf
New Member
I bought it knowing I would get much less than the rated 5A balancing on new cells. I hoped it would keep my expensive cells going longer in a very high drain environment (50Ahr on a 2KW inverter). I know the multitude of electrolytic capacitors would also wear out long before the cells did (or so I thought). My initial concern was keeping a good top balance. Now that I put the project to use I could easily have left the cells to cycle 60-70% for longevity, and only fully charge the battery when rarely needed for longer operating.
I bench tested the balancer when I got it by unbalancing cells and monitoring current with my Fluke Amp Clamp. It worked moving current. It did have a high pitch whine from an electronic component. I asked the seller who replied it is normal (I no longer believe anything the seller writes). My battery is a 2P8S LiFePO prismatic cells brand new (in July) Fortune Chinese made from a USA distributor. I finished the battery build in early October 2020.
I left it in my battery pack for less than 2 months without checking it. When I checked it 2 days ago the cells were dead. When I removed the balancer the voltages slowly climbed back up clearly indicating a significant load was removed. I am sure the balancer contributed to the failure. A cell could have gone bad and taken the rest with it, but the balancer does not work as the seller described.
I had some back and forth with the seller about the function. He said at 3.0V it shuts itself off and pulls 0.1mA. I observed the LED go out at about 3.0V cell voltage, but it appears to still be draining my other battery I am testing it on now. I now regret not buying a better balance, but it likely will not fit my case.
I bench tested the balancer when I got it by unbalancing cells and monitoring current with my Fluke Amp Clamp. It worked moving current. It did have a high pitch whine from an electronic component. I asked the seller who replied it is normal (I no longer believe anything the seller writes). My battery is a 2P8S LiFePO prismatic cells brand new (in July) Fortune Chinese made from a USA distributor. I finished the battery build in early October 2020.
I left it in my battery pack for less than 2 months without checking it. When I checked it 2 days ago the cells were dead. When I removed the balancer the voltages slowly climbed back up clearly indicating a significant load was removed. I am sure the balancer contributed to the failure. A cell could have gone bad and taken the rest with it, but the balancer does not work as the seller described.
I had some back and forth with the seller about the function. He said at 3.0V it shuts itself off and pulls 0.1mA. I observed the LED go out at about 3.0V cell voltage, but it appears to still be draining my other battery I am testing it on now. I now regret not buying a better balance, but it likely will not fit my case.
Last edited:
I bought one of these during the ‘Black Friday Sale’ on AliExpress and it should arrive by February.
You’re experience is a good warning, but I was not planning to leave it connected permanently.
I build my 8S batteries with a parallel 8S monitoring harness where I can connect a BattGO monitor and my plan was to occassionally (quarterly?) connect the 5A Active Balancer to than monitoring harness and charge the battery all the way up the knee past 3.55V (where voltage differences get hugely amplified).
I then planned to disconnect the Balancer until next time but your unfortunate experience will make doubly-sure I do so..,
Steve_S
Offgrid Cabineer, N.E. Ontario, Canada
There are many Active Balancers and they are chemistry sensitive. Some can do different chemistries with settings, others have jumpers, some are ordered for a specific chemistry, such as LTO or LFP. Make the wrong choice & use it on your batteries and the results can be drastic.
NOT ALL BALANCERS are created equal and there is some real CRAP out there being flogged.
Known Good are Deligreen's QNBBM's and Heltec
Battery Equalizer-Battery Accessories-Deligreen Products (deligreenpower.com)
Chengdu Heltec Automation Technology Co., Ltd. - LoRa Nodes, LoRa Gateway (alibaba.com)