electric moped fault

billyboya

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Ok start again, in all there are 14 pins call Black wire no 1 pin which initially is B0 or 0v (it carries no voltage) , the next Yellow no 2 pin is cell group #1 and the next Red no 3 pin is cell group # 2 and so on until you get to the 14th pin which is cell group #13. The 13 Yellow/Red wires are the 13 cell groups.
#1 cell group is pin 2 yellow wire so Red probe on pin 2 & Blk probe on pin 1.
#2 cell group is pin 3 Red wire so Red probe on pin 3 & Blk probe on Yellow wire before it.
#3 cell group is pin 4 Yellow wire so Red probe on pin 4 & Blk probe on Red wire before it.
#4 cell group is pin 5 Red wire so Red probe on pin 5 & Blk probe on Yellow wire before it.
#5 cell group is pin 6 Yellow wire so Red probe on pin 6 & Blk probe on Red wire before it.
#6 cell group is pin 7 Red wire so Red probe on pin 7 & Blk probe on Yellow before it and so on and so on until you get to the very end where #13 cell group is pin 14 Yellow so Red probe on pin 14 and Blk probe on the Red pin before it .
Alternating one should get 13 cell readings of 3.81v or 3.82v or similar if they are all balanced.
Hi Nealh I found this much easier, now. ok I have done it 2 ways like you said above. the 1st way I set meter at 20V. pin in black wire 1st pin then pin in next to black. then held black probe on pin 1 red probe on pin 2.
then I moved pin 2 to pin 3. and pin 1 to pin 2, and carried on until 13 was tested.

so like 1st pin 2nd pin = #1 = 4.19v

2nd pin 3rd pin = #2 = 4.19v

3rd pin 4th pin = #3 = 0.30v but slowly was going up

4th pin 5th pin = #4 = 0v

5th pin 6th pin = #5 = 3.89v

6th pin 7th pin = #6 = 4.16v

7th pin 8th pin = #7 = 4.19v

8th pin 9th pin = #8 = 4.11v

9th pin 10th pin = #9 = 4.11v

10th pin 11th pin = #10 = 4.11v

11th pin 12th pin = #11 = 4.11v

12th pin 13th pin = #12 = 4.11v

13th pin 14th pin = #13 = 3.97V


I did get a puff of smoke when I tested 2 pins above, maybe I pressed needles on too deep

Then I tried the other way you said put meter on 200V pin in 1 then pin in 2, left pin in 1 and placed 2 in 3 &4 &5 and so on until pin 14

readings below

#1 = 04.2v
#2 = 08.4v
#3 = 08.8v
#4 = 07.9v
#5 = 17.1v
#6 = 21.3v
#7 = 25.5v
#8 = 29.6v
#9 = 33.7v
#10 = 37.8v
#11 = 42.0v
#12 = 46.1v
#13 = 50.1v

I've also tested battery from discharge side its 49.2V


I dont think this plug is safe now as when that puff of smoke happened I must have pushed in pins too far to cause wires to burn

IMG_2427.jpg
 
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soundwave

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cell banks 3 and 4 are toast no way to bring them back now cut main power cables from the bms as it is not safe! and put it outside asap
 
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Nealh

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Yep your battery is toast as SW has put it, as expected the liitokala's for there very cheap price use very suspect cells or very poor BMS. I would say you got your moneys worth but it is a price not worth paying.
Cell group #3 & #4 have bit the dust.

The battery is only fit for recycling, if you have a use for the other cells one can cut them out for reuse but not much cop for torch use.

Thoeretically one could clean the cells up and try and make another battery to gain some knowledge and experience, a new BMS of better quality will be needed. There are enough cells to make a 48v/13s 5p battery or a 36v/10s 6p or two smaller lightweight packs.

As already said how on earth you guys pay silly money for 78 cell 21700 battery and expect quality god only knows. Pucker 21700 cells are min £4 wholesale or £9 retail.
 

billyboya

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Yep your battery is toast as SW has put it, as expected the liitokala's for there very cheap price use very suspect cells or very poor BMS. I would say you got your moneys worth but it is a price not worth paying.
Cell group #3 & #4 have bit the dust.

The battery is only fit for recycling, if you have a use for the other cells one can cut them out for reuse but not much cop for torch use.

Thoeretically one could clean the cells up and try and make another battery to gain some knowledge and experience, a new BMS of better quality will be needed. There are enough cells to make a 48v/13s 5p battery or a 36v/10s 6p or two smaller lightweight packs.

As already said how on earth you guys pay silly money for 78 cell 21700 battery and expect quality god only knows. Decent 21700 cells are min £4 wholesale or £9 retail.
Ok I gathered as much cells 3 & 4 are toast. would it be in my best interest to find a cheap 48V battery. then sell moped. or sell for spares or repair . I would rather sell as working order, as cant see no one buying this as spares or repair
 

billyboya

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cell banks 3 and 4 are toast no way to bring them back now cut main power cables from the bms as it is not safe! and put it outside asap

When you say cut main power cable from BMS which are they as I dont want this battery stuck in my flat if its dangerous Ive seen some explode can you say in my images what wires to cut and will it start to spark
 

soundwave

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id just cut your losses and get rid of it and dont buy cheap batts from china it is not worth your house burning down.

cut the cables on the left and right of the bms and remove the balance cable and do it outside!!!
 

billyboya

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Aug 10, 2016
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Yep your battery is toast as SW has put it, as expected the liitokala's for there very cheap price use very suspect cells or very poor BMS. I would say you got your moneys worth but it is a price not worth paying.
Cell group #3 & #4 have bit the dust.

The battery is only fit for recycling, if you have a use for the other cells one can cut them out for reuse but not much cop for torch use.

Thoeretically one could clean the cells up and try and make another battery to gain some knowledge and experience, a new BMS of better quality will be needed. There are enough cells to make a 48v/13s 5p battery or a 36v/10s 6p or two smaller lightweight packs.

As already said how on earth you guys pay silly money for 78 cell 21700 battery and expect quality god only knows. Pucker 21700 cells are min £4 wholesale or £9 retail.

I wont have thought £176 was cheap as that's what I paid 9 month ago Ive a good mind to send seller a message on Aliexpress but is it worth it
 

billyboya

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id just cut your losses and get rid of it and dont buy cheap batts from china it is not worth your house burning down.

cut the cables on the left and right of the bms and remove the balance cable and do it outside!!!

will this spark if I do that as cant have a fire starting. do you mean where I have marked in yellow



2.jpg
 

soundwave

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soundwave

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yes cut them all off and deactivate that bomb ;)
 

billyboya

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yes cut them all off and deactivate that bomb ;)
Well a good mind to sling that sod over a wall LOL pissing great £176 down the frigging drain Plus all the work Ive done on this moped it wont sell as spares or repair now

Bomb deactivated



bomb.jpg
 
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soundwave

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the other cells look ok so you could still use them and get a cheap 18650 charger for about 10 quid on ebay


 

billyboya

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the other cells look ok so you could still use them and get a cheap 18650 charger for about 10 quid on ebay


Nar I wont ever use those anyway best to dump the frigging battery plus moped too. I spent about 5 months getting this to go and really thought once i got battery and all was running ok that was it. I should have sold it ages back. but Hey we all make mistakes as the hedgehog said to the wire brush

no sod is going to buy this now as spares or repair. or pay out for a battery for it. and I have spent enough on it now. so I would just be losing out if even I bought another battery which wont be cheap. I could have bought a new electric bike what I've spent on this moped.

do you think also I should cut all those red yellow wires on bms plug too

Are well its goodbye billyboya from now on that will please a few now Im not running on about my moped. But its all been a learning curve. even my brother said I should have got an electric bike

sound of a trumpet blowing
 
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Nealh

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Cut or desolder the Black negative wires one at a time and tape the end up.

The positves all eminate direct off the battery cell group #13 and the cell groups. One thick wire is for the discharge connector , another for the charge connector.
 

Nealh

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Desolder the sense wires from the battery it self or cut one at time as near to the battey cells as poss.
 
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soundwave

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everyone cheeps out on the batt as dont want to pay 4 5 600 quid but at the end of the day this is the power supply for the bike and one of the most expensive components.

when you buy ready built batts from china you have no idea what cells or bms they are using and works ok for a while then cell banks go out of wack and have the same problem you now have.

your lucky it never went on fire as it was trying to blow up or let rip inside the moped but lesson now learned ;)
 

billyboya

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Cut or desolder the Black negative wires one at a time and tape the end up.

The positves all eminate direct off the battery cell group #13 and the cell groups. One thick wire is for the discharge connector , another for the charge connector.

Did you not read or see my last posts above Ive cut all wires to battery now, well to BMS do you think I should also cut thta white plug with all those 14 wires 1 black and others red and yellow
 

soundwave

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yes cut all the cables off it inc the sense cables where soldered to the cells
 

billyboya

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Desolder the sense wires from the battery it self or cut one at time as near to the battey cells as poss.
I didnt have time to desolder LOL I just cut through all wires from BMS plus I will now also cut that white plug going to BMS the one with yellow red wires