Battery not charging, new battery has no Smart BMS

[juhuri]

So my wife's battery wouldn't charge anymore, works otherwise still.
So I bought a new battery, which charges so the charger is fine.

Old battery had "smart bms" sticker on it an the new one doesn't.

Opening up these batteries I saw that old battery has 5/5 pins connected and the new one only 3/5.

I was thinking about either transferring the old the board (BMS?) to new battery, or connecting the rest pins on the new one.

Here's some pictures, do you think one of the alternatives could work?









Motor: Bafang 8fun 250w, SWXK37V250W (13), 1412169637
Led display: SWXK S27309150201 (2015-01)
Controller: LSW93 6-8, C87050 17-04-28B2, 37v, max 12A, Rated 6A, Low voltage protection 31V
Battery: JCEB360-8.8 Joycube DC36.0V 8.8Ah 316.8Wh. With "Smart-BMS Battery" sticker (new battery the same, but without BMS sticker)

 

[docw009]

Those look like well made packs. Leave them alone. The wiring is different.

 

[juhuri]

What I forgot to mention and what is the main problem is that new battery isn’t working with the controller. That’s the reason I’m planning to do some modifications to the new battery.

 

[e-beach]

What I forgot to mention and what is the main problem is that new battery isn’t working with the controller. ....

Can you explain that more fully? How is it not working? It came with the battery didn't it?

 

[juhuri]

Sorry, I'm probably mixing up some terms.

When I'm putting the new battery in my ebike, I get error codes in the led display, where I would select assist levels and power on the bike. Motor wont start.
Service manual for this bike says that Error code 2, which I get, can be caused by problem in contacts between battery and controller.

So I'm guessing this is because the bikes controller is not getting some needed signals from the battery as there are three pins that are not connected inside the battery. Connected are only + and - and 3rd one (green), I guess is the back light (integrated in the battery). Back light turns on from the led display, works on new battery also.

In the old battery all 5 pins/contacts go somewhere.

 

[e-beach]

If you can trace the wiring and be sure you are wiring to a proper part of the circuit, that I would encourage it, but if you are not 100% percent sure what you are wiring to then it is a roll of the dice.

 

[docw009]

OK. I ses what you're saying. Old battery won't charge but runs bike. New battery won't run bike, because it's the wrong one, missing 3 contacts.

You propose to use the entire electronics from old battery with new cells. Well, first you should determine why the old battery didn't charge. It's either some failed cells or a failed BMS. If it's the latter, then you wasted your time moving the cells.

I would run a voltmeter across all 10 parallel groups and see what the voltages are, looking for evidence of a failed cell (abnormally low voltage).

 

[sleepy_tired]

Try contacting the manufacturer. They might have a good suggestion.

Swapping out the controlller, for example, so it's compatible with the new battery might be a option.

 

[juhuri]

I didn’t feel that confident doing soldering myself. So I took the batteries to a local shop specializing in renewing batteries. (To put the old bms in the new battery). Should be ready next week. Let’s see if it works.

 

[juhuri]

Try contacting the manufacturer. They might have a good suggestion.

Swapping out the controlller, for example, so it's compatible with the new battery might be a option.

I considered replacing the controller as well. But finding one that works with my current led display, pas and motor was a consern. I don’t know how universal these things are. Do they all communicate with each other?

 

[juhuri]

BMS board taken from old battery to new.
Charges and works well

 

[AngryBob]

I would like to thank you and express my appreciation for your coming back and filling in the information of the conclusion to your problem, confirming what the actual problem was and verifying that the proposed solution was effective.

So very, VERY many people fail to do this very important step, leaving no conclusion, verifying no solution, and making the entire exchange useless and non-informational.

Kudos to you sir, you are a good man.