DIY Li-Ion rechargeable battery pack

[scottjua]

Question:

Can I take the two trustfire 14500s I got from TCSS... charge them one by one first, then wire them together, heatshrink them, and voila I have a battery pack???

Is it this simple?

[LUMINARA UNDULI]

Pretty much :D.

[Gil Gamesh]

Question:

Can I take the two trustfire 14500s I got from TCSS... charge them one by one first, then wire them together, heatshrink them, and voila I have a battery pack???

Is it this simple?

week late, but yup, it's that simple.  Some prefer to use the PCB's, but personally I've always made packs like how you said, and have only had an issue once where one of the batteries got borked.  Pretty good ratio of success to fail over the last few years!

[smaneesint]

I know this thread has been posted since 2009, but I wanna thank you for making this topic! As an overseas buyer, I cannot order any completed battery so I'll have to make one myself. 

[mikestar007]

I'm actually curious now that's it's been a few years , have those packs with individual protected cells in them maintained their balance and runtime?

[eastern57]

Ooh, good question, Mike.  The longest standing project that I have right now is my iron man hilt (jan 2012), it still runs great with the AW 14500 pack.  I have other projects that use AWs from even earlier, but I have forgotten which hilts they are in.  Regardless, the fact that I've lost track should be a testament to the fact that I can rely on them to work - even after I've pulled them out of old project hilts. 

On the other hand, Trustfires and Ultrafires eventually fizzle out. They either lose the ability to charge, or their output goes to crap.  But AW/Panasonic seem to go the distance.

[mikestar007]

That's great! I was a little on the fence about making a pack with two protected cells for my saber. Thanks for the reassurance.

[Withengar]

Hello, I am trying to build a 7.4V pack and i've question.
In Azmaria Dei guide for building a Li-Ion battery Pack it is stated that discharging a Li ion cell to a value below 2.7V increases the risks of damaging the cell. Reading through some PCB data sheets I've noticed that they either feature an over discharge voltage value of 3V or a much lower value between 2.2 or 2.5. So if a 3.0V is used the pack will not discharge completely and more frequent recharges will be required, but there is (almost) no risk of damaging the pack, while if the 2.2-2.5 is used the pack will last longer before it runs out but the excessive draining will reduce the pack's longevity.
Is this correct? And which is the way to go?