I've had my battery on charge, on and off, all day and it's still registering nothing. its about two years old and not had heavy use. I always recharge after I've used it but have laft it standing for some months (since last Autumn) without a recharge every couple of months?(as recommended by the manufacturer on the side of the case - which I have only just read!). If its dead, is there a way to open up the case and replace the batteries inside? I'm sure I read something on Pedelecs a couple of years ago about that.

Your battery won't be dead. Your BMS (battery management system) has switched it off for whatever reason.

Have a look at this thread, where Mxer125 had the same problem. If that doesn't work, you can take the top and bottom off the battery, slide the contents out and check the individual cell voltages with a voltmeter. That will give a clue to what's wrong.

http://www.pedelecs.co.uk/forum/electric-bicycles/14558-possible-check-individual-cells-while-tab-welded.html

Thanks for this. Sorry for the delay in replying. Find navigating around the forum confusing. Will try what has been recommended and get back.

Forgot to mention that there's two fuses in the battery. Check the charging fuse. I think it's inside the battery.

Can you send a blow by blow account of how to open up a battery? Many thanks.

Four screws on the top and four on the bottom. Pull the top and bottom away, then you can see what's what. You can slide the contents out but it might be held with a bit of glue. When you reassemble, put some packing at the top to stop the cell-pack from jumping up and down.

Thanks d8veh.

we bought a new one in the end (£189), which is a shame as the cells where perfectly ok i'm thinking the BMS went on ours (same as you sat around in winter) it does wake up with a bit of tinkering but in our case only for a few hours then it shuts down again:(....

I'm still in the middle of finding out why ? but will need to replace and check all the wiring which may take some time and as we have no need for it now i might break it down and reconfigure to 48v if i find any more cells..

so if you can't get yours going again and decide a new one is needed i would like to have yours of you for some beer tokens ...

 

I took ours apart exacly how d8veh explained, you need to carefuly chip away the brittle glue then slide outof the bottom turning the top so it fit's through the ally case,

Once out then cut the tape to the insulation board unfold to expose all the cells and bms, The way i woke my bms up strangly was to disconnect the ballance tabs and then plug the charger in for a few seconds, then disconnect then plug ballance wires in again, Stange but worked for me ??...

 

check all fuses and wiring continuity for any faults, this is as far as i got but still no joy with ours, Just stays alive for couple hours then goes again, strangly down the 13v Hope you have more luck then us and have fun!!!...