Rawkkrawler
1 mW
Hope this lands in the correct sub thread...
A little background. I've balanced several E-scooter batteries with success, but this latest issue is puzzling me.
This battery comes from an Apollo Phantom V2 E-scooter. I recently purchased two as a package knowing the batteries weren't great.
After removing the plug to the BMS, and metering out each cell pack, I found a low of 3.66 all the way up to 4.2. Just as i suspected.
I also use just basic equipment. A desktop charger, and a Fluke meter. I successfully balanced all packs to reach 58.7 volts.
So the problem..
Going for a quick test ride, about 6-8 miles, the battery quickly dropped to the cutoff and left me stranded.
I actually did this twice, using the chassis of each of the identical scooters to rule out hardware outside of the battery.
I was half way expecting that a cell pack or two dropped off and triggered the BMS to shut off, all cell packs are within .02 volts.
The obvious answer was that multiple cells within a pack weren't provided the capacity as they should but voltage is fine.
If this were the case, should i be surprised that the voltage across all 14 packs are identical?
So the question..
What could be the culprit, and what tools should i purchase to isolate the problem? And could it be a bad BMS? I'd doubt that.
Thanks!
Mike
A little background. I've balanced several E-scooter batteries with success, but this latest issue is puzzling me.
This battery comes from an Apollo Phantom V2 E-scooter. I recently purchased two as a package knowing the batteries weren't great.
After removing the plug to the BMS, and metering out each cell pack, I found a low of 3.66 all the way up to 4.2. Just as i suspected.
I also use just basic equipment. A desktop charger, and a Fluke meter. I successfully balanced all packs to reach 58.7 volts.
So the problem..
Going for a quick test ride, about 6-8 miles, the battery quickly dropped to the cutoff and left me stranded.
I actually did this twice, using the chassis of each of the identical scooters to rule out hardware outside of the battery.
I was half way expecting that a cell pack or two dropped off and triggered the BMS to shut off, all cell packs are within .02 volts.
The obvious answer was that multiple cells within a pack weren't provided the capacity as they should but voltage is fine.
If this were the case, should i be surprised that the voltage across all 14 packs are identical?
So the question..
What could be the culprit, and what tools should i purchase to isolate the problem? And could it be a bad BMS? I'd doubt that.
Thanks!
Mike