rick kimura

Hi , ive got a problem im hoping isn't serious and its to do with my battery . Today I removed the battery from my bike and connected it up to another ebike . When it was connected to the other bike nothing happened so I immediately disconnected it . I pushed the button on the battery to see if the green bars lit but only a red light comes on now .
There was no smell indicating something burnt out and no noise . I checked the fuse and the wire isn't burnt out so im stuck hoping I haven't ruined the battery ,,,,any suggestions ?

rick kimura

Also to mention ,, the battery is a lifepo4 48v . The fuse may have been burnt out on the end and I couldn't see it but it looks ok except for a slight brown tinge on the glass . If it is the fuse there,s nothing on it to say what type it is .

Dave Cutter

So... should we assume that you knew the other ebike didn't work/had a battery problem? And I would then assume that you've also tried the other ebikes battery in your bike... and it doesn't work ether? So now your wondering if the other bike has some defect that could killed a battery is a mere minute?

It isn't likely that your battery has been truly killed. Fuses blow/trip due to a fault/short. I'd guess the (evil battery killing) ebike is drawing a big load and getting hot somewhere (not shorting).... which is melting a heat sensor in the battery pack.

2old

Rick, as indicated above, it doesn't seem as though you ruined your battery connecting it to another bike. Easiest thing to try is replace the fuse and try the battery in the previous system. If that doesn't work, you might consider recharge since it may have been dormant for awhile (give it enough time to balance) and try again.

rick kimura

Gday bob , My battery was fully charged ,,,but I will try your suggestion . Ill try another fuse / let it sit on the charge for a while and see what happens . I bought a complete ebike 250w 36v (dying battery) for $250 . The motor and everything else is good so ,,,,,stupidly I used my good battery to try it out . I don't know how or why this happened as there is no burnt smell , it was switched on for 1 second before I turned it off , and it was in my garage ! I cant understand how the 36v 250w bike could have damaged my 48v battery ,,,,If anything , I thought the controller would have popped (not my battery)

rick

rick kimura

thanks to dave cutter and 2 old , the battery problem has been fixed . I pulled the bms off the top of the cell and when I turned it over ,,,the underside of the printed circuit had a burned 3mm foil track going to what I suspected to be the power supply . I took it to a guy I know who repairs guitar amps and he resoldered it . Its now back on the bike and going as it did before this happened . I also took it to a battery shop where they checked the cell and they told me it was unharmed by the fizzle on the BMS ,,,. All is good !
rick

2old

Rick, great job correcting the problem. Ron (spinningmagnets on ES) has an interesting article in electricbike today. He stated that many battery problems were BMS related.

rick kimura

Yeah , thanks bob . I don't doubt that problems being BMS related as the BMS has the power to shut down the battery over very minor things . I would imagine many a good repairable battery has been trashed due to a bms related problem . I was about to throw mine out and was on the verge of spending the bucks on a new one . Glad I pulled it apart and did the final visual check ,,, it paid off !
rick

spectastic

so the battery shorted and burnt a wire inside... I wonder why it didn't trip the fuse first.

also, I would be cautious with the other bike that you put the battery in. there's obviously an exposed wire somewhere in the controller or power wire that's shorting out the battery

rick kimura

Hi spectastic , I was lucky that it was a minor repair and I found it . Ive learnt a lesson that could have been cost me considerably more , from now on its caution