I want to do some diagnostics to see what might be going on with the 36v16ah lithium battery from Golden Motor. To do a proper investigation I felt it was important to also pull it out of the aluminum housing to examine the inside thoroughly. To do that, I had to unscrew the four screws securing each of the end caps (4 on each cap), and had to push it out one side. I push from the side opposite of the
BMS controller. It seemed that it was stuck and would not move. It appears they have used some double sided thin black cushioning foam (about 1/16 of an inch along parts of each side. I used a screw driver to help break the stick of this foam. Although it was still causing sticking. I used two squared sticks and lodged them against the side, on the plastic frames surrounding the battery cells. It was still tough to push through, but was able to slowly get it out. The assembly looked find, no water or burning indications. I did notice a bit of solder or metalic flakes on the sticky side of the paper covering the
BMS. I used magnifying glass to find and remove as much of them as I could as I was concerned that these could break loose of contact metal on the
BMS. And it is possible that this may have happen. I tested the 10 sets of 4 cells. And they all presented a 4.19 voltage. So at this point it seems that everything is fine. Perhaps there is other testing I can do to identify why I am not able to get more than 200 watt/hours out of this 580 watt/hour battery pack, and it only having about 500 charge cycles, most of which have been at less than about 40 percent discharge. And it seems that the loss of capacity happen fairly suddenly about 20 charge cycles ago, from about 570 watt hours, then only getting about 200 watt hours.
In any case I thought you guys might appreciate a picture of the insides of the battery pack. And I welcome your feedback. And if there is someone from Golden Motor seeing this, Can you assist in getting this issue resolve.
