How to assemble to many batteries without solderin

[VidPro]

Into One big arse one (the weird way)

1) first you take a bunch of batteries out of some project a manufacturer discarded.
in this case some 1100-1200ma LI-ION cells

i got these a long time ago, and was running a lectric scooter with them


2) Build yourself some sort of box, that will not bend to much, and that fits the batteries

at the bottom put 1" closed cell foam, or any ol foam that will have some pressure, as oppsed to going completly flat.

3) Get some metal screen materials, preferably brass, or copper , good luck finding anything descent out there. cut them close, then fold the edges to fit your box perfectally.
the material MUST be flexable, and should not be strong or pointey enough to go through the batteries top insulations, you will achieve a direct SHORT of the whole thing if you go through the insulation on the top wrap around the bottom jacket of the battery. (that was Important)

4) Sand the side that will be connecting to the battery, Oxides of metals are not conducters usually, so lightly sand the metal mesh.

5) Strip the connecting wires the whole distance of the box, and spread them out like hair across the whole box. use reletive size of wire for your charging and discharging load.

6)The wire goes next to the batteries, then the mesh, then the foam. they do not have to CONNECT to everything, they are just getting the power from the mesh, which DOES.

7) put the batteries in the box

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8) put your other blond wig connetor on the top of the batteries.


9) preferably none of your wire, pokes itself into where it can connect to the negative or bottom side of the battery, by getting poked in by the tab top, if it does, it will light up, and be gone fast enough i didnt have any problem with this at all, but its a possibility

10) put that top screen on, with its sanded and flatest side down

11) put the top foam on, which should fit perfectally, and provide a fair ammount of force when the lid is closed.

12) hold the lid down with something, preferably a hasp or something.

now you can ACCESS this pile of garbage any time you desire.
add or subtract batteries, check them, change them, move the whole thing, it is portable now.

13) i Always try and cut the End leads of high power stuff DIFFERENT lengths, they are far less likely to find eachother that way. (see you did learn something after all

This particular one is about 100A at 3.2-4.2V it will (hopefully) be charged at 6A, and drawn off at only 10A.

this is for a solar LED project thing.

 

[Mike Painter]

Interesting.
I would have been tempted to use a tube of some sort to obtain a more uniform force and higher voltages.
If any (acidic) moisture gets in you will probably start haveing interesting problems.

 

[MrAl]

Hello there,

Hey that's neat /ubbthreads/images/graemlins/smile.gif

Im surprized to see so many batteries put in parallel like
that, but if that's what you need and it works ok i guess
you got what you were after.
You may find that you have to replace the screens or
re-sand them after a while as there could be some oxidation
after some period of time.


Very interesting!

Take care,
Al

 

[VidPro]

i was wondering about that, aluminum oxide is non conductive.
but so too is steel rust, and anything else that connects to batteries in flashlights.

i wonder if the point of contact will be closed enough that it wont go bad at that point.
or if i should put some conductive slime in or something.

i couldnt find the brass or copper screen that i went for, or any other materials that would form a proper mesh blanket.

the bottom cells connections are even with thier insulation, so whatever it was, it had to actually push up twards the cell.

 

[VidPro]

Yes mike, it is usually preferable to have some kinda voltage. luckily at least with liion its not 1.5v

so if i stack 4 of these up add in some Real wire, i could use it for a 12v solar thing.

its just that lead acid doesnt LAST and it doesnt like to be left discharged, so i hate them.
but i might hate these too

its just a test solar, charge it up during the day, use it on LEDs at night, no funkey circuit stuff needed if i do it exactally right.

 

[snakebite]

what did that pack come from?
how are you going to protect it?
better yet how was it originaly protected?

 

[MrTwoTone]

This may be a dumb question,what's going to happen if one of your cells should short internally?With a 100 amps available things could get interesting pretty quickly.Just a thought-Dean

 

[VidPro]

when one shorted internally it heated up to like 300-500*f melted the insulation off which was 2 seconds from connecting the whole pack to itself using the batteries metal jacket.
i pulled it out

it should have vented, and venting would have disconnected it making it a open curcuit. i opened it up to look inside, and the vent was intact, the electrolyte roll was browner in the center.

 

[VidPro]

the pack came from a manufacturers failed product, or a bunch of them in this case. they had protection circuits.
my protection will be a fuse, and voltage charge regulation. or max possible voltage charge, or cut off voltage charge, nothing else.
the draw off will be leds, and when they are very very low, the current draw is so low, that dropping the pack to 0 (again) would be near impossible.

 

[VidPro]

the alternative is soldering or "tabbing" the whole thing together, which will result in the same electrical charachteristics. just not the insulation peel off connection problem.
with them soldered, it is impossible to tell what is wrong, a dead cell, or anything.
with this (weird insane) method, i can open the top, and check each batterywith a single probe.

 

[Zelandeth]

Clever idea. Think you'd be a lot safer using a metal box with a suitable liner though, in case something did go wrong. That thing could prove to be a pretty nasty fire risk as it stands.

 

[VidPro]

yes, and aluminum case, that would work good for heat dissipation also.