Build Your Own Li-Ion Battery Packs from Leftovers – Tutorial
Posted in Tutorials by Bill
19 Jan 2010
All right folks. The attached is my first attempt at writing a tutorial, so go easy. It goes over how I turned Li-Ion packs from obsolete equipment into usable packs for my SAGAR robot. For about $10 per pack, I built my own 14.4V 2.2Ah Li-ion pack, and in the attached pdf, I show you how I did it, so you can do it too.
Quick note for the Hack-a-day crowd. The PCB does in fact handle charge leveling across the individual cells. All you need is a smart charger like this, and you are good to go. For a more in-depth look on soldering directly to cells (not recommended, but if there’s no other option), I recommend this tutorial, although I’m still not brave enough to do it myself. I’ll stick with my tabbed cells.
Download: DIY Li-Ion Tutorial
Here is a pack in my SAGAR robot I’m building.(click to enlarge)
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12 Comments.
Hey!
oh and nice that you made it to hackaday!
thanks for the great how to, thats just what I needed for my new project, talking about perfect timing, im trying to do something similar and i have to do custom battery packs for a handheld console
Btw. how are you thinking of charging these batterypacks?
Greetings from Denmark
[...] your own lithium-ion batteries – [Link] Tags: Batteries, Battery, LiIon Filed in DIY | 1 views No Comments [...]
I charge the batteries with this:
http://www.all-battery.com/universalfastsmarttlp3000chargerforli-ionli-polymerbatterypack148v4cells.aspx
nice work, i did this once as a remake of a laptop battery, and i’m goin that path again now that my satellite has a dead one
[...] The second runs the scrolling marquee hanging off my chest. Everything is run off a 14.4V Li-Ion battery pack that I custom built. Even the LED Marquee is custom [...]
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I work for the cable company and have piles of cable modem batteries identical to the ones in your tutorial. I purchased this board to protect it with:
http://www.batteryjunction.com/li-pcb-14v4–.html
Wired it up, I can place my volt meter at the points on the board and they add up correctly.
Except no power comes out of the main leads from the board. The total voltage off the batteries going into the board as around 14v. Is there something I am missing? Assuming I wired it up correctly if my batteries were over powered or under powered would the board shut the power down? And how could I fix this? I ordered 3 boards and have tried it with 3 different sets of batteries.
Have you tried connecting the pack to a charger? Sometimes the boards lock up and wont reset until a voltage is applied the load side of the protection board.
Yes, I have a charger and when I plug it in it goes green for about half a sec then red. I thought I had it over chargerd. So I drained it down with a fan some. Plugged it back into the charger with the same results.
Weird, haven’t seen that before. You may have gotten bad boards, that’s all I can think of.
So if the batteries were drained, the charger still wouldn’t say charging for more then a second?
Yeah. same with all the batteries. One set was brand new never used. Even after I drain it some, it will not take a charge.
Hello Bill,
What is the best way to test the individual cells before you connect them together?
I have read that in most cases the whole battery pack will not charge, when in fact it could be just one or more cells?
Thanks
Joe