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?
I bought one of these during the ‘Black Friday Sale’ on AliExpress and it should arrive by February.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.
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.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.