Lipo sparks.... Help

[dimpirate]

Putting together a 24S 4P of 8s 5.8Ah lipo packs.
Separated packs into 3 separate 4 packs.
The 8S packs have two separate 4S balance taps.
So...

What did I do wrong..... Grabbed 1st 4 packs. Took 1 4s tap out of each into one of methods LVC/HVC parallel boards. Started plugging in 2nd set of taps from same 4 packs. Once second tap got plugged. Sparks!
I did have the first LVC/HVC board balancing at the time could that have caused it?
Or am I doing this completely wrong.....

Thanks for any help...

 

[wesnewell]

Sounds to me like you got the high/low taps crossed. Easy to do if you haven't color coded them. I'm curious why you chose those 8s packs to begin with. 24s4p would have been much simpler using 6s packs or even 4s packs as I use. With them it's easy to make 12s packs that can be charged with a 12s balance charger. You can't do that with the 8s packs. I use 4s packs but had to make balance adapter cables to turn the 3 4s plugs into 2 6s plugs. 6s packs would have been easier, but the 4s hardcase packs are really cheap by comparison. I'm guessing using 6s packs would been cheaper than using the 8s packs too. For charging I just split the 24s into 12s packs and charge as 12s4p.

 

[ian.mich]

Sounds to me like you got the high/low taps crossed. Easy to do if you haven't color coded them. I'm curious why you chose those 8s packs to begin with. 24s4p would have been much simpler using 6s packs or even 4s packs as I use. With them it's easy to make 12s packs that can be charged with a 12s balance charger. You can't do that with the 8s packs. I use 4s packs but had to make balance adapter cables to turn the 3 4s plugs into 2 6s plugs. 6s packs would have been easier, but the 4s hardcase packs are really cheap by comparison. I'm guessing using 6s packs would been cheaper than using the 8s packs too. For charging I just split the 24s into 12s packs and charge as 12s4p.

The 8S packs use 2x 5-pin (4S) JST connectors do they not? Can still use isolated balance chargers (BC168) on the JST ports with your harness that turns his 6x 4S connectors into 4x 6S.

 

[atom1025]

Sounds like you connected cells 1-4 then parallelled cells 5-8 onto that. The cells can't be in series and parallel together. Each 8s pack needs two boards not one.

You'd plug 1-4 into one board and then 5-8 into another board.

 

[atom1025]

Also beware that the board you zapped is probably shorted, do not plug anything into it until you assure that there's no continuity between pins 1-5.

I'm assuming you bought 3 boards and one hvc breaker. For your setup you need 6 boards and one breaker.

I feel your pain as lipo mistakes can cost big money and another $150 on boards was a surprise I imagine.

The cheaper route would of been 6s packs. Then only 4 boards would be needed.

Adam

 

[MadRhino]

4s, 6s, 8s... Who cares, it doesn't make any difference apart the number of connectors that you have to use. The less power connectors and the bigger the wire, the better it is for performance and reliability. With Lipo, bulk charging is best and the less often you have to undo the connectors, the better it is. I have Lipos that had been balanced only twice in over 400 cycles. Let me comfort you that the 8s 5800mah Zippy compact is a very good choice. I have used many of them and have had even better reliability than with the 6s of the same cells that are very good already.

If you understand your battery chemistry and your equipment, you won't make any stupid mistakes. With Lipo, you HAVE to understand BEFORE using them. Take the time to learn, double check and make sure. Lipos are for conscious people. A BMS is not a solution for Lipo IMO (sorry Methods, I know many are asking for it and I have to give you credit for you are doing a very good job to help). Nevertheless, with Lipo the user has to be the BMS himself, if he can't he should use another chemistry. Just my 2 cents, never trust anything else than your own careful supervision with a chemistry that will catch fire if not managed properly.

 

[Ykick]

4s, 6s, 8s... Who cares, it doesn't make any difference apart the number of connectors that you have to use. The less power connectors and the bigger the wire, the better it is for performance and reliability. With Lipo, bulk charging is best and the less often you have to undo the connectors, the better it is. I have Lipos that had been balanced only twice in over 400 cycles. Let me comfort you that the 8s 5800mah Zippy compact is a very good choice. I have used many of them and have had even better reliability than with the 6s of the same cells that are very good already.

If you understand your battery chemistry and your equipment, you won't make any stupid mistakes. With Lipo, you HAVE to understand BEFORE using them. Take the time to learn, double check and make sure. Lipos are for conscious people. A BMS is not a solution for Lipo IMO (sorry Methods, I know many are asking for it and I have to give you credit for you are doing a very good job to help). Nevertheless, with Lipo the user has to be the BMS himself, if he can't he should use another chemistry. Just my 2 cents, never trust anything else than your own careful supervision with a chemistry that will catch fire if not managed properly.

This is so true!

Hell, the solvent used in these things is similar to Tolulene or some hot paint thinner. Any form of ignition is almost guaranteed to burn!

 

[cassschr1]

Did patrick ever make the 8s boards? Said he was going to. If he did I would change the balance taps on the packs to a 8s ( 9 wires). ALSO ,i BET SOME BALANCE WIRES ARE FRIED INSIDE NOW.

 

[dimpirate]

Yes that was the problem, I didn't know the separate 4S balance taps had positive and negative. Good thing I got extra pack... Had to do a bit of connector swapping and soldering ( extra good pack had bad connector from earlier frock up).
So glad it worked in end.
I got to tell you seeing wires melt and sparks all around has got to be the most depressing ebike experience ever

I am using 6 HVC/LVC boards, methods included a few extra boards just in case of sparks. So sparkies got swapped.
Only reason I'm using these 8s packs is because of fit.
I'm using a phasor frame and methods controller inside, one of the only solutions I found to get at least 100V 20AH.
Most 6s packs are to wide to have 2 side by side in frame, well I can blame it on the packs all I want but that controller is frigin huge.
So the 8S fit very tightly( that was quite a mission) the plus is there 5.8ah so I get 23.2 total Ah
And 12 packs instead of 16 (6S).

Few pics


View attachment 2

 

[shock]

Nice Bike is that a custom frame?

 

[dimpirate]

Phasorcycles.com
There's also a thread in picture video section