sams
Well-known member
Like many people I killed my cheap Ni-cads in no time for my drill. Being the forgetfull type and not having an auto off does that. So over time I repacked my cheapo Ryobi 14.4V with various options each with a greater success. It went in this order:
- 12 x Ni-mh AA cells soldered in series: worked ok for quite a while but I had some issues with cells eventually, I don't think they liked the high current load or being soldered. Gave a reasonable increase in torque.
- 4 x 3.6V Lithium Ion cells out of a laptop battery taken apart: very good gain in torque over the Ni-mh cells and lasted quite a reasonable time per charge, I only used this a very short time before converting my second battery pack to whats below;
- 8 x 3.6V lithium cells as above but 4 pairs in series for a total of 8 (2P x 4S): this gave the same torque as above however the charge life was very long, it was about 6x the original pack. This went well and all but it didn't take long to start showing signs of dying. I think it was the combination of too much current and me doing the poor practice of charging all the cells in series without equalising the individual cell voltages.
- Lastly the next step was a huge upgrade, I used one of these:
It's a 5A/h 14.8V Lithium Polymer/Li-Po battery pack made for large aeroplanes and simular.
http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=9177
It was cheap and easy to source from the above link. I had to chop two holes in both ends of the battery housing to fit it in however I plan on making an Aluminium enclousure to house it. With 5A/h compared to the 1.5 - 2A/h that's normal on the top end drills and my original of 1.2A/h it has some serious storage. The torque increase was so massive that I literally burnt part of my hand when trying to stop it in the faster gear when before I could do so with my index finger and thumb previously. I have been concerned about breaking the gearbox with the sheer extra grunt but so far it's held up. I gave it hell and tried drilling a 10mm (3/8") hole through a thick steel plate. I came to a point where it got hot enough that a small amount of smoke came out. So it's obviously working much harder than it's designed for, this is ok though as I just let it cool down a bit before getting to this point, I use the heat of the handle to know. I still manage to do a lot of work with it though and I did my kitchen with it winding screws into some very hard old framework wood.
I have also done the same thing with my dewalt drill, cordless angle grinder, dewalt drill, dewalt impact gun, leaf blower and line trimmer.
If people are interested I can post more of my experiences with those and show some pics.
- 12 x Ni-mh AA cells soldered in series: worked ok for quite a while but I had some issues with cells eventually, I don't think they liked the high current load or being soldered. Gave a reasonable increase in torque.
- 4 x 3.6V Lithium Ion cells out of a laptop battery taken apart: very good gain in torque over the Ni-mh cells and lasted quite a reasonable time per charge, I only used this a very short time before converting my second battery pack to whats below;
- 8 x 3.6V lithium cells as above but 4 pairs in series for a total of 8 (2P x 4S): this gave the same torque as above however the charge life was very long, it was about 6x the original pack. This went well and all but it didn't take long to start showing signs of dying. I think it was the combination of too much current and me doing the poor practice of charging all the cells in series without equalising the individual cell voltages.
- Lastly the next step was a huge upgrade, I used one of these:
It's a 5A/h 14.8V Lithium Polymer/Li-Po battery pack made for large aeroplanes and simular.
http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=9177
It was cheap and easy to source from the above link. I had to chop two holes in both ends of the battery housing to fit it in however I plan on making an Aluminium enclousure to house it. With 5A/h compared to the 1.5 - 2A/h that's normal on the top end drills and my original of 1.2A/h it has some serious storage. The torque increase was so massive that I literally burnt part of my hand when trying to stop it in the faster gear when before I could do so with my index finger and thumb previously. I have been concerned about breaking the gearbox with the sheer extra grunt but so far it's held up. I gave it hell and tried drilling a 10mm (3/8") hole through a thick steel plate. I came to a point where it got hot enough that a small amount of smoke came out. So it's obviously working much harder than it's designed for, this is ok though as I just let it cool down a bit before getting to this point, I use the heat of the handle to know. I still manage to do a lot of work with it though and I did my kitchen with it winding screws into some very hard old framework wood.
I have also done the same thing with my dewalt drill, cordless angle grinder, dewalt drill, dewalt impact gun, leaf blower and line trimmer.
If people are interested I can post more of my experiences with those and show some pics.
