14.8V Li-ion Battery Pack Diagram?

**Master Valon** · 03-19-2011, 05:45 PM

Hello again fellow saber enthusiasts! Sorry for the flurry of posts from me, asking electronic wiring questions. I just finally ordered all of my parts for my 10W ledengin stunt saber, so I just want to be ready when it all comes. I was wondering if anyone has any pics of when they wired together 4 Li-ion cells and a PCB, as that's the only aspect of this build I'm not 100% on. I'm gunna be using 4 14650 cells in double barrel setup to give 14.8V to a 1000mA Puck and 10W Deep Red led (W/ recharge port.) I have scoured these and other forums and have yet to find a pictured tutorial involving making a 4-cell Li-ion pack. Thanks for reading this all the way through!

**Azmaria Dei** · 03-19-2011, 06:32 PM

the 14.8V battery pack is set up the same way as the 7.4V packs, just with more cells. here's a picture of wiring an example 14.8V PCB.

**Master Valon** · 03-19-2011, 08:30 PM

Thanks as usual Az! You always seem to have the perfect answer for me, lol. Thanks bunches!

**Azmaria Dei** · 03-19-2011, 08:47 PM

i do try. ^_^

**dbluephoenix** · 03-28-2011, 01:47 PM

With this, would you be able/need to use the 4AA or 6AA battery holder, or would you just wire each battery directly to the chip? Also, as I understand it, you'd have to wire your batteries in Parallel in order to get any longevity benefit. Does the chip already sort of do that?

**Tanimal** · 03-28-2011, 04:54 PM

Originally Posted by dbluephoenix

With this, would you be able/need to use the 4AA or 6AA battery holder, or would you just wire each battery directly to the chip? Also, as I understand it, you'd have to wire your batteries in Parallel in order to get any longevity benefit. Does the chip already sort of do that?

I'm pretty sure thats not true. The mAH rating of your battery pack will raise with how many batteries you have no matter how you arrange them.

**Master Valon** · 03-28-2011, 06:09 PM

Well first off, you would need a AA sized 14500 cell to make the pack from, in order to use those holders. (I'm personally using 14650 cells, which are 7/5 the size of AAs). Plus, if I remember correctly, those AA sized cells in the store are "protected" and as such, DO NOT use a PCB with them, as that would be bad. Lastly, yes you do wire each battery directly to the PCB, but you also wire them to each other. This means that except for two cells in the pack, on each terminal of each battery there will be two wires, one going to a terminal on the board and one going to the next cell. And from my understanding, wiring in series, which is what you have to do for this pack, makes VOLTAGE additive, whereas wiring in parallel makes CURRENT additive(again if I remember correctly). And no, the PCB does not add any longevity bonus to your pack- all it does is monitor charge/discharge rates, as Li-ion cells are notoriously unstable with out such safeguards. Hopefully this helps you guys out, as I just used this knowledge provided by this and other threads here to successfully make my first Li-ion pack(14.8V). Happy sabersmithing!

**Azmaria Dei** · 03-28-2011, 10:00 PM

with batteries wired in series, the voltage goes up with each added cell, but the mAh stays the same. wired in parallel, the voltage stays the same, but the mAh goes up.

that PCB can accept series/parallel combination wiring, but you would have to wire the same number of and type of cells to each position.

as for using the battery holder, skip it and heatshrink the batteries together with the PCB.

as for protected vs unprotected, use unprotected batteries when building packs. using protected batteries adds a whole level of butthurtz to convert them and is a lot of hassle. trust me on that - i've done it several times. oh and to further convince you, if you screw up when you're converting it, it turns into a grenade and you can lose body parts. grounding the connectors together without a PCB causes a short which causes massive current flow which causes swelling which causes the casing to split which causes the lithium to come into contact with air, which causes a violent explosion. never puncture a Li-Ion cell either, by the way.