View Full Version : Modifying nimh batteries

11-08-2006, 06:07 PM
I bought myself the ICS ak74 along with a custom ak battery that i thought would fit into the stock without having to modify it. So Im wondering if its safe to remove a single cell from the battery pack so I can make it fit into the stock. This is the battery I have,


I want to take out the singled out cell thats on the tip. If i do this will it be less than 9.6v?

Dark Paladin
11-08-2006, 06:33 PM
Yes. Each cell is 1.2v. 8 cells = 9.6v. 7 cells = 8.4v.

11-08-2006, 10:44 PM
Unless you have an upgraded spring, 8.4V should be able to fire the AK with a slightly lower rate of fire.

"-Custom work and modification might be required to fit." <---- 'might' == always :P

11-08-2006, 11:01 PM
When you solder battery packs, make sure you have a decently powered soldering iron, but more importantly you want to use a wide flat tip so that heat can be transferred quickly to solder the wires on. Too thin or small of a tip means you have to apply heat for a longer period which conducts to the internals of the cell, possibly causing damage. Battery cells do not like heat.

11-08-2006, 11:51 PM
AustinWolv offers sage advice; the metal end caps on rechargable cells cover a thin plastic insulating ring that is easily melted with prolonged heating. Not to mention, the heat can damage the rest of the cell's construction. You'll want at least a 50W soldering iron to do the job.

Here's a great video on how to properly solder battery tags: http://www.batterieswholesale.com/download/soldering.wmv

Now, on to your particular situation. Judging from the pictures, you've lucked out. After carefully cutting away the shrink tubing off the protruding cell, de-solder the wire and/or battery tags from the cell. Solder these two connectors together in however you see fit, taking care to keep the soldering iron away from the end cell. Cover your work with several layers of electrical tape and you're done.

11-08-2006, 11:57 PM
Village, nice link!

The other tidbit I neglected, but picked up from the R/C world, is to very finely sand the metal endcap. Just a little bit. This allows better surface for the solder to grab versus smooth surface.

Found another link: http://findarticles.com/p/articles/mi_qa3819/is_200001/ai_n8901462