EGO Battery with bad BMS

[Surferdudemi]

I've got a 5AH EGO 56v battery that won't charge, but if you charge the battery (after opening it up), it's fine. So it appears that the BMS failed or has some problem. Anyone have experience with this? I don't see any obvious issues like broken wires or scorched components.

 

[MaikaiLife]

I've encountered a similar issue with EG4 batteries. A client brought me three LifePower4 batteries that wouldn't accept a charge through the main battery posts. I removed the lids and directly charged the cells with a 48V charger for about 30 minutes. After this, I tested to see if flipping the on switch would activate the BMS. It worked; the BMS came online, and I was able to complete charging the batteries through the main posts. The client is now using these batteries in their off-grid solar system.

Sometimes, there are no visible signs of issues with electronics. It's possible they could be software-bricked or have an internal failure that's not physically apparent.

When you say the battery works if you charge the cells directly, do you mean the rest of the battery's functions are fine, but that you cannot charge the battery once it's entirely dead without opening it?

 

[Solar Guppy]

Pretty common for the EGO batteries and there isn't a repair service for them that I known of to replace the BMS

 

[Surferdudemi]

I've encountered a similar issue with EG4 batteries. A client brought me three LifePower4 batteries that wouldn't accept a charge through the main battery posts. I removed the lids and directly charged the cells with a 48V charger for about 30 minutes. After this, I tested to see if flipping the on switch would activate the BMS. It worked; the BMS came online, and I was able to complete charging the batteries through the main posts. The client is now using these batteries in their off-grid solar system.

Sometimes, there are no visible signs of issues with electronics. It's possible they could be software-bricked or have an internal failure that's not physically apparent.

When you say the battery works if you charge the cells directly, do you mean the rest of the battery's functions are fine, but that you cannot charge the battery once it's entirely dead without opening it?

Yes. I can charge the battery by bypassing the BMS. It can then be used in my mower just fine. I don't know if the BMS is in the discharge chain, or if it only manages charging. I would think it's in the discharge chain to avoid over-discharge and manage temperature.