electric moped fault

[Nealh]

I have already mentioned 49.7v is an average of 3.82v per cell if they are balanced, however I expect you may have a low cell group so the charger will remain green and the bms won't switch to allow the current to flow. We did warn you about the liitokala being cheap and suspect when you bought it and pretty sure we mentioned you may run into issues with it.

As SW also mentions you will have to open the pack to find the bms and take 13 seperate cell group voltage readings, those may or may not tell you where the fault lies.
If the 13 reading are all good then the bms is likely faulty and will need replacing

 

[billyboya]

I have already mentioned 49.7v is an average of 3.82v per cell if they are balanced, however I expect you may have a low cell group so the charger will remain green and the bms won't switch to allow the current to flow. We did warn you about the liitokala being cheap and suspect when you bought it and pretty sure we mentioned you may run into issues with it.

As SW also mentions you will have to open the pack to find the bms and take 13 seperate cell group voltage readings, those may or may not tell you where the fault lies.
If the 13 reading are all good then the bms is likely faulty and will need replacing

Yeah I must have forgot what you said. about that battery its only 9 months old. its a pity really as I cant sell it as working now. so looks as if i am going to have to sell as spares or repair. as I cant see any 48V batteries to fit the moped. if it wasn't too expensive I would get another battery. at least then I can sell as working, or just go down the road as selling it as spares or repair.. as I cant go opening this battery now and messing with the BMS. say I decide to get a new battery 48V would you advise it. at least then I could sell it for more as working moped.

I expect even if I bought a battery from UK it would have came from china

can you suggest what's best a new battery or sell as spares or repair

 

[billyboya]

you need to test the cell bank voltages it wont charge because there is a problem with the batt.

Are well cant go opening this battery as too much messing about. and cant guarantee I can sort it.

 

[guerney]

I don't fancy having to do this myself, but will certainly have a go if needed - a BMS was replaced recently on this thread:

Bbs01b died or so it seems

Hey, I've been rebuilding an old Kudos Eiger with a new bafang mid drive. Id put it all together and when I eased on the throttle the screen went off like it reset, so I tried again and as soon as I put load on the motor the screen died. And now the screen is dead, no response, I checked all...

www.pedelecs.co.uk

 

[soundwave]

id just get rid of it and sell for spares or repair as a new batt from the uk will cost a fortune if jimmy makes it.

 

[billyboya]

id just get rid of it and sell for spares or repair as a new batt from the uk will cost a fortune if jimmy makes it.

whos jimmy LOL

Well they say you have to speculate to accumulate. But a 48V batt would it be worth it, mine you at least I would be able to sell for more. but as for spares or repair wont get sod all.

Well Ive just seen a 48V charger 54.6V output for just £15 now would that be worth getting

 

[billyboya]

I don't fancy having to do this myself, but will certainly have a go if needed - a BMS was replaced recently on this thread:

Bbs01b died or so it seems

Hey, I've been rebuilding an old Kudos Eiger with a new bafang mid drive. Id put it all together and when I eased on the throttle the screen went off like it reset, so I tried again and as soon as I put load on the motor the screen died. And now the screen is dead, no response, I checked all...

www.pedelecs.co.uk

what does this do then as wont have thought it would recover mine LOL. it looks just like a normal charger

Home :: Accessories :: 0V Recovery Charger

Use this to recover your battery if it has not been used or charged over a long duration of time you only need to use this charger one time and then a normal charger can be used The 0V charger will only recover a battery with voltage from 22V to 27V cut off voltage You should measure the voltage...

starkdrive.bike

 

[soundwave]

no idea but says max 27v you can recover the cells voltage but if they have been hammered it wont last long.

1-24S Battery Voltage Display - Awesome tool for batteryrepair!

www.pedelecs.co.uk

 

[billyboya]

no idea but says max 27v you can recover the cells voltage but if they have been hammered it wont last long.

1-24S Battery Voltage Display - Awesome tool for batteryrepair!

www.pedelecs.co.uk

looks a handy tool ok if you know what you doing, and is it worth it. ok if you doing loads of batteries.

 

[soundwave]

they use fake cells as thats why there cheap and also a fire hazard as if the pack gets to hot because it cant do the amps needed it will explode.

Buy 18650, 21700, 20700 and 26650 Batteries online | Fogstar UK

We’re the UK’s leading retailer of 18650, 21700, 20700 and 26650 batteries. Buy online now for fast delivery.

www.fogstar.co.uk

 

[billyboya]

they use fake cells as thats why there cheap and also a fire hazard as if the pack gets to hot because it cant do the amps needed it will explode.

Buy 18650, 21700, 20700 and 26650 Batteries online | Fogstar UK

We’re the UK’s leading retailer of 18650, 21700, 20700 and 26650 batteries. Buy online now for fast delivery.

www.fogstar.co.uk

What’s this web site as can’t see any 48v batteries

 

[soundwave]

they sell single cells not complete batts.

eBike Batteries

ebikebatteries.co.uk

he can custom make any size batt and in the uk and will have warranty

 

[billyboya]

they sell single cells not complete batts.

eBike Batteries

ebikebatteries.co.uk

he can custom make any size batt and in the uk and will have warranty

Well I am seriously thinking about checking inside battery as if it could be repaired say like it needs a BMS are they expensive

As all I have done to this moped seems a shame now to sell for spares or repair plus I would at least have a good working moped to sell

I have tested a BMS well back on this forum when I 1st got moped I tested that battery BMS but obviously that battery wasn’t right for the moped so I think I will at least give it a go if anyone willing to give me some help. Can’t do any harm if I fail at least I would have tried

 

[soundwave]

bms will be 30 quid but if a cell bank has gone bad you need to remove the cells and spot weld in new ones.

the problem doing this is the cells will be mismatched ie new cells and old mixed together so if the other cells in the pack are fake then you could loose another cell group and be back to square one.

 

[billyboya]

bms will be 30 quid but if a cell bank has gone bad you need to remove the cells and spot weld in new ones.

the problem doing this is the cells will be mismatched ie new cells and old mixed together so if the other cells in the pack are fake then you could loose another cell group and be back to square one.

Well £30 isn’t bad for a BMS and like u said if it’s a cell bank well that’s it. I think if I can get battery going at least I’ve tried plus all a learning curve I’m no hurry anyway plus I would be able to sell for more than spares or repair

But would need to remove shrink wrap 1st can you buy that blue wrap as it’s just like normal shrink wrap what you heat with hair dryer or what ever

I may look for a job mending electric mopeds ha ha ha well I would have had enough bloody experience

 

[guerney]

what does this do then as wont have thought it would recover mine LOL. it looks just like a normal charger

Home :: Accessories :: 0V Recovery Charger

Use this to recover your battery if it has not been used or charged over a long duration of time you only need to use this charger one time and then a normal charger can be used The 0V charger will only recover a battery with voltage from 22V to 27V cut off voltage You should measure the voltage...

starkdrive.bike

He replaced the BMS at the end of the thread, which might be worth doing, if it turns out that you need to?

Bbs01b died or so it seems

Hey, I've been rebuilding an old Kudos Eiger with a new bafang mid drive. Id put it all together and when I eased on the throttle the screen went off like it reset, so I tried again and as soon as I put load on the motor the screen died. And now the screen is dead, no response, I checked all...

www.pedelecs.co.uk

 

[guerney]

Well I am seriously thinking about checking inside battery as if it could be repaired say like it needs a BMS are they expensive

As all I have done to this moped seems a shame now to sell for spares or repair plus I would at least have a good working moped to sell

I have tested a BMS well back on this forum when I 1st got moped I tested that battery BMS but obviously that battery wasn’t right for the moped so I think I will at least give it a go if anyone willing to give me some help. Can’t do any harm if I fail at least I would have tried

I reckon you'll fall in love with your Erider 15 all over again after it's fixed and keep it. It's gotta be those curves or something

Avoid getting electrocuted.

 

[billyboya]

I reckon you'll fall in love with your Erider 15 all over again after it's fixed and keep it. It's gotta be those curves or something

Ya having a laugh no way will I be keeping it. As had a good 5 months at repairing it. But learnt loads from here Nealh and Matthewskack have been great in helping. Just hope getting battery sorted which Honestly never expected to have to check. But at least if it’s not gonna cost too much well it’s worth trying and if I can’t well that’s it. But shame moped has been running over a week on its stand I mean I have tested it every day just to see and all good but now need batt sorting as can’t sell with out it

I will when I get more time look inside battery soon

ILL B BACK lol

 

[Nealh]

Spending another £200 on a battery doesn't mean you will get £200 for the bike when working so it is either cut your losses now or attempt to opene the battery to repair it.
You have thus far learnt and managed to carry out work you never dreamed of before , the battery is a piece of cake to check cell voltage and if you can solder well a bms is that daunting.
As with the rest of work you have carried out we can give advice on what to do.
One can get a bms for approx. £15 - £25.

 

[Nealh]

I think you paid approx. £90 for the liitokala, we said at the time it will be fake or poor cells used. It may be the cheap electronics used otherwise known as the bms, pay cheap pay twice.
My next battery build is a simple 12s 2p build with 21700 cells, 24 of them are £106 on there own and are one of the best cells avialable.