How to Turn 100 leetel batteries into . . .

[Psycogeek]

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
   
   

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.

[hiker]

why not use tinfoil or copper sheeting on top and bottom of batts?

with foam --for pressure..

   whats it going to be used for?

[hiker]

forget that question --i see you have the wire mesh their.................

[Psycogeek]

its for my solar test project thing.

the hope is to charge this pack with no regulation no circuits whatsoever, to its max of 4.25v, ok so i will use 1 DIODE :-) 10x.5 solor cells

then discharge it with a 10X 3W luxeon LEDs , which will replace a chandelier light that uses 8X25W chandilier bulbs.  with no circuits, resisters, or things that lose power, other than the copper wire <1ohm

[JeroenH]

the hope is to charge this pack with no regulation no circuits whatsoever

Be VERY careful about charging (and discharging also) Li-ion cells without some form of charge regulation. While NiMh/Lead-Acid batteries may sputter and die when you mistreat them Li-ion cells WILL burn and/or explode.

Look up some more info. You will find some useful stuff here: http://www.batteryuniversity.com/

Another thing (just a tip): wouldn't you rather arrange them in strings of 3 cells in series? That way you'd have about 3 x 3,7 = 11,1V, lots of 12V stuff should be able to run off it. In case of your LED lights, you'd be able to run several LEDs in series, reducing current and increasing efficiency (and/or allowing you to use thinner wires).

[Psycogeek]

yes, all that you have said is 100% correct, it would be better. . . BUT

these mondo leds will take an overvoltage without any problems when heat synced, and i am using the 3W ones that not only want more voltage, but will run at a lower voltage too.  when the pack goes down, the light NEVER really dies, the current drops and it should run for a long time on this pack i made.

The LEDS WILL indeed easily be placed in series, to use higher voltages, with the exact same effect. like a 14.4v series set of them.

i do run them banked in all the 12v type lights i have in them now.

but them darn LI-ION cells as you have pointed out will CROAK die fail miserably (thanks to the blasted goverment regs) when they go over the voltage , they wont burn or explode, because on a SINGLE venting they die, and i cannot get the venting disconnect to re-connect :-(  although it would be fun to make them burn and explode :-)

so if they step to far over the 4.25 the whole pack will be dead, i have been testing a bunch of them that were thrown out from laptops and stuff.

 MOST of a "Pack" of lithiums that was deemed bad was still good, just a few series cells vented.  total waste.

in other words, most tossed lithiums are GOOD, and it was the pack problems that killed them.

so if i put them in series, instead of this mondo block i have to have charge circuits for every one of them, and that means some sort of reduced efficiency, as high as -20%.

with this ONE cell , i have none of the problems, no circuit stuff that i couldnt build anyways :-) no offset cells or reverse charging.

in other words other then the voltage MAX, And excessive currents, and line voltage drop, and , there would be no problems.

i would certannly not try and run or light the whole house with any type of system like this, but it is perfect for my testing.

also this block could be charged at 50AMPS, and drawn off at 100A and it would still enjoy it , it can be brought down to 1V, and it will love it, it can be left down for months, and still come back when charged, and its self discharge is very low.

its almost like nothing can go wrong

SO

i will tell you as soon as as it DOES go wrong :-)

if they can make it i can break it, and durn well put it back together again :-)

[Psycogeek]

i forgot one thing.

IF the solar voltage will possibly get over the 4.3v that i intend to stop the charging at, there are two ways to do a cut off charging on them.

they have solid state relays (very minor consumption) that trigger at almost that exact voltage. and they have 6 V relays that trigger at that same voltage.

so if the solar panels manage to ever be that good (in that dream world) i could implement one simple cut off , without electronics expertise.

[Psycogeek]

Ahh crud

the whole 100-140A pack has a 1/2AH self discharge :-(

I will need about 12A a day just to keep it topped off

that means a

3A solar cell set would lose 4 hours just to self discharge

6A 2 hours

12A 1 hour

the AVERAGE sun time full powered solar operation is 6 hours a day

so with a

3A system 2/3rds of it will be wasted

6A system 1/3rd of it wasted

12A system 1/6th of it wasted

guess that determines how much solar juice i need.