Dead Li-Ion battery woes

[bluesoleli]

Hi Everyone,

Just purchased a cheap e-bike on eBay with the intention to use it as a daily while I sell off my CNE bike bit on the Giant and make it a normal pedal bike again. I will keep the 36V Li-Ion battery from the CNE kit and use it as a backup as they go for quite a bit of cash.

The bike I picked up is similar to the Beyond Oil bikes (decent bikes). It's a step through frame and the brand is Progear, model E80 from 2012. 200W rear wheel hub with a 36V silverfish Li-Ion battery. Final price I paid was $165. Reason? it's like new (used a few times) but with a dead battery because owner left it in a shed for too long and it went completely flat and won't charge.

Battery is about $310 but doesn't bother me as I'll wire my CNE bike 36V battery in and use that instead (strap it to the rack in an eZee battery bag - ugly but works). However, it would be good to get the original battery going again if possible (two batteries wired in parallel, yo). I dunno how "possible" this will be as I heard completely dead batteries become dead because the BMS has no power to control the charging?

How possible is it to revive the dead battery?

Thanks.

 

[dnmun]

you have to post up pictures of the battery and the charger showing the labels so we know what the voltage is for the charger and then open the battery case and remove the battery so we can inspect it. do you have a voltmeter?

 

[bluesoleli]

Yeah I have a voltmeter. My trusty Fluke always sits on my desk. My bike is currently being shipped from down south so I'll have to wait for a few days before I get it and crack the battery open as well as see the charger for the first time. Will definitely keep everyone updated.

 

[dnmun]

sometimes it is the first few cells which get drained down so low the BMS cannot turn on enuff to allow current to flow into the pack and those cells are a lot outa balance too so you would need to charge them up to the level of the others in the pack which were not drained down by the circuit current of the BMS. but a lot of the time lithium ion has a short life cycle so they don't come back as easily as the lifepo4. but you can buy new cells and replace the bad ones so it may not be too expensive to restore it to close to full capacity.

 

[motomech]

My first Ebike Battery was a "top shelf" Lithium Ion, which was dead within the first year. The bike was being shipped internationaly when it got stuck in a warehouse for a couple of months. When I finally received the bike, it read 0 Volts. I checked the Voltage in front of the BMS and it too read 0 Volts. A very expensive paperweight!(and lesson learned)

 

[bluesoleli]

Got the bike a few days ago and cracked the battery open with a voltmeter. 0V the whole way through the pack, not looking good at all.