Just hooked up batteries and got a good spark

I just tried to hook up some newly shipped (from Hobby King) Zippy 6s 5000mah lipos in series using a series harness from EP Buddy. Both batteries were at about 53% as shipped and cells were balanced separately, then together before hooked up. The EP Buddy harness is pretty much idiot proof but I got a very good spark when I made the last connection, the all red jumper wire. Spark was good enough that I now cannot get a good female onto the sparked male, nor the sparked female onto a good male. Both are black on the inside though the plastic is not melted; I jumped and the connection did not stay together.

One possibly very important note: I had the balance plugs wired in together in parallel using another harness. Was this a big no-no? I've seen many packs on this site, mainly 12s2p (my final goal here) where all four batteries' balance leads were wired together in parallel. My thought was if one can do that then the balance leads from any one battery can be paralleled with any other battery's in the 12s2p pack. Wrong assumption?

Both batteries seem fine; still balanced, same voltages as before, etc. The series harness might be best replaced though...

That's a monstrous no-no.
You shorted the batteries together.

You can't connect the cells in parallel and connect the main batteries in serial.

Did you also discharge test the batteries before OKing them for use?

Ok. Bad idea.

How is it possible then to have all the batteries in a 12s2p pack (made from 6s batteries) have the balance leads all paralleled using a 6 --> 1 harness (utilizing only 4 of the 6)? It seemed odd to me when I saw it in the "Lipo Plug and Harness Service For Lipo Virgins" post (and then in other posts) but I figured that if all four could be connected, two would not be a problem.

Uh oh. That image is what a battery short in the making looks like. Did you take that picture or was it on that thread?
I think somebody has improperly educated you and that is a problem.

You can charge like that with a 12s pack; turning a series group into parallel to use a 6s charger...
but you absolutely need the balance leads in the appropriate configuration.

So if you are charging a 12s2p pack as a 6s4p pack, you need the balance leads either disconnected entirely or them in parallel..

When you are done charging and want to put it on the bike, you take that 6s4p pack and convert it from a big parallel group to a smaller serial group of 12s2p. The balance leads will need to be in a serial connection or you will short the battery as you did.

You then need two balance lead harnesses, one on each 6s2p group.
Does that make any sense to you?

Sounds like a lipo fire in the makings. I would cover the basic wiring tutorials if I were you, and read up on proper lipo care.

What I don't understand is how are all the balance wires not burned to shreds in that picture... :lol: :lol: :lol:

^-- me either! But it is hard to determine what's connecting to where.

I actually blew up an iCharger balance board doing something like that. The iCharger got knocked out of calibration super hard too. I am surprised it still works!

Here is a visualization for you.

no spark here i guess i lucked out on my first try :wink: am i seeing things or are the balance leads all together?


[youtube]tpA7eyRwPnA[/youtube]

Ok well now I'm confused. It seems that 'karma' is saying it's possible, though it's hard to tell whether it's sarcastic or not.

The image I posted is from the thread "Lipo Plug and Harness Service For Lipo Virgins", under Battery Technology, midway down the second page.
I've also seen similar setups in other discussions: all balance leads joining into one set. Cruel/dangerous prank or reality (or some sort of misunderstanding on my part)?

Either way, it should NOT be a problem to parallel 2 6s 5000mah packs to make a 6s 10000mah pack, parallel those balance leads, make a second identical pack, series those two together (discharge leads only) making a 12s2p 10ah pack. And use a Hyperion 1420 charger to charge the pack as one big beast, with each combined 6s balance lead going to each of the Hyperion's balance ports. Correct or no? This was my original plan.

Like this but with each battery being made up of two 6s 5000mah in parallel:

Either way, it should NOT be a problem to parallel 2 6s 5000mah packs to make a 6s 10000mah pack, parallel those balance leads, make a second identical pack, series those two together (discharge leads only) making a 12s2p 10ah pack. And use a Hyperion 1420 charger to charge the pack as one big beast, with each combined 6s balance lead going to each of the Hyperion's balance ports. Correct or no? This was my original plan.

Click to expand...

Absolutely correct. I do exactly the same thing with my Hyperion 14s. The charger recognizes the balance leads coming from the first 6s and the 2nd 6s.

Just make sure you never combine parallel leads with different voltage potentials.

heh no nothing sarcastic. im new to this myself. but looking at that charger setup a and b are isolated from each other inside the charge for monitoring and balancing only. if a and b where tied together wouldn't that make it a dead short?

karma said:

heh no nothing sarcastic. im new to this myself. but looking at that charger setup a and b are isolated from each other inside the charge for monitoring and balancing only. if a and b where tied together wouldn't that make it a dead short?

Click to expand...

Right I guess. I thought you were saying in your original post that you had a four battery pack that was both parallel and series AND that all four batteries balance leads were combined.

The difference here is that the hyperion balance charges, and the paralleling board (or harness) paralells.Very very different.

I don't see exactly how you have the balance leads and power leads connected karma, so i can't say.

But the overriding theme here is that the balance leads need to either be disconnected, or follow the parallel or serial scheme that the lipos are wired in.

This is how my 10s 4p pack looks:



If you are not doing some parallel to series type charging scheme, your pack should look like this 100% of the time.

BTW the spark does not happen until you connect the oh oh shit wire



Then you get Kentucky fried connector..

Those balance curcits. Aren't they supose to help manage the batteries and help save things. See what voltage the packs are ? Good Luck

In case it's not been completey made clear to other guys new to lipo.

You CAN paralell balance leads on packs that are paralell connected. Whether the connection is permanent or temporary, packs of the same number of cells, for example 5 s, can have the main leads parallel connected AND the balance leads paralell connected.

What you CAN NOT DO, is paralell the balance leads when the packs are connected in series. For example, two 5s packs are connected + to - making it into a 10s pack. Now if you paralell those balance leads, they will short the pack and spark, melt wires etc. You just connected a 10s battery with a 5s battery.

To paralell connect, the batteries must be the same voltage.

Just to add, even if you KNOW all these things, constantly reconfiguring packs, you WILL forget a connection or mess up and do some short circuiting. God knows i have....