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Deep Discharged Battery Fix?

Old 01-02-15, 08:35 AM
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Deep Discharged Battery Fix?

Greetings, I'm new here.

I let my batteries go into deep discharge, partly through neglect and partly through a 2 month trip outside the country where I couldn't charge my battery. So, this one is on me. Here's the quick stats:

ebike system: Bionx 48v SL 350 HT XL

-According to this web page (Using BionX diagnostic mode), I have the following:
-1.4 volts (00014) in the battery. ouch. Is that at least a record?
-Error Code 25 (low voltage).
-25.8v DC out of the charger.

Can you recommend a fix or product? Warranty has expired. I've talked to several online retailers who haven't offered much help. I also took my battery to Batteries Plus (local battery/electronics store) and they won't touch the battery pack.

I'd like to consider all options, including DIY projects, before I give up. I probably won't be buying another Bionx system.

Many thanks!
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Old 01-02-15, 11:20 AM
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If you have some knowledge of electronics and batteries and testing equipment and soldering capabilities, you could try tearing the battery unit part. It's possible not all of the cells are damaged, and only a few that are not able to hold a charge. At 25.8v, it looks maybe 1/2 of the cell clusters (cells in parallel) are not holding charge or dead, but also possible only a cell or two in that cluster may be totally dead dragging down that cluster.

It's a bit of technical detective work, but considering the price of brand new battery pack might be worth the time if you only need to replace a few cells.

... a note of caution ... messing around with and charging batteries can be very dangerous - overheating and exploding batteries are a possibility, so do it only if you know what you are doing ...

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Old 01-02-15, 12:09 PM
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25.8v out of the "charger" is correct, it's actually just a 26v converter... the charger is inside the battery. maybe you could try something like this, tho it may not work on the 48v battery. BionX Battery Recovery I too recommend some caution when charging... I would phone/send the battery to BionX myself...

EDIT; After reading the BionX battery recovery page, I see it says not to use on 48v batteries for some reason... Phone BionX support...

Last edited by 350htrr; 01-02-15 at 12:20 PM.
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