Having some issues with by BBSHD kit

mangekyo

New Member
I ordered a complete 1000w Bafang BBSHD kit with a 48v 17.5ah battery and a dcp18 display from China.

I did a lot of research before choosing the display, battery and BBSHD. I actually wanted a 52v battery, but from what I read, the dcp18 display is inaccurate with a 52v battery, so I went with a 48v battery instead. I was also worried about longevity of the motor, so I figured its better to be safe.

I haven't started to install the motor kit on my bike frame, I just connected the battery to the motor and the display and I connected the throttle just to check if everything is working. I have encountered som issues.

My battery although it is according to the seller, 48v 17.5ah with 18650 Samsung cells, it only charges up to 54.1v. Is it acceptable for a brand new battery? I'm worried that since the battery already has degraded by 0.5v, maybe it will not last as long as it should. Seller says its normal. It also drops to 53.6v within a couple hours when turned off and not used.

When my battery is fully charged, the display shows 65% battery remaining. From what I read, this wasn't supposed to happen with a 48v battery, only with a 52v battery. But my seller says it's the opposite. A 52v battery will show accurate readings on the display, while a 48v battery will be inaccurate. Is this true?

EDIT: Now my seller is telling me that Bafang has upgraded to a 52v controller, so thats why my I'm having battery compatibility problems. Is this true? Any way to verify that the controller is 52v? And even if it is, does that mean the display cant show accurate readings for 48v battery, just because the controller is 52v?

It actually says 48v 1000w on the bottom of the motor, when I showed it to the seller they said its 48v and 52v universal. Dont know what thats supposed to mean, but anyway. I should be getting correct battery readings with a 48v battery right? So since I am not, it means that either Something is wrong with the battery, the display or the controller itself, right?
 
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AHicks

Well-Known Member
Display battery meters are notoriously inaccurate.

54.1 v is maybe a hair off, but fine. Could be the BMS or the charger shutting it down a little early. No big deal.

The fact it's dropping voltage after sitting for a while could be that the cells aren't totally balanced yet. Again, not that unusual. They'll most likely align better after the battery has been discharged and allowed to completely recharge a few times (to the point the charger shuts off), allowing the BMS time to balance the cells correctly.

Put it together and go ride!