On Fri, May 17, 2019 at 3:05 AM Erik Christiansen <[email protected]> wrote:
> On 16.05.19 23:25, andy pugh wrote: > > On Thu, 16 May 2019 at 23:07, Chris Albertson <[email protected] > > > > wrote: > > > > > > > ill never beat Tesla's price. Even if you build a factory and mass > > > produce them > > > > > > So, let's turn that on its head. How can I run my cordless tools from > Tesla > > cells... > > IIRC, the individual cells¹ are around 3.2 or 3.4v, so 4 would make a > 12v pack, 6 for 18v, etc. Since their form factor probably won't suit an > existing tool, it's either fabricate a new battery compartment, or run a > cable to a pack on your belt or the floor. (I was going to do the latter > with a small spare 12v lead acid battery, but in the end fitted an even > smaller one into the existing battery compartment. It's adequate for the > small jobs I use the cordless for.) > Almost all power tools use packs of cylindrical batteries. The batteries come in a standardized size. Cheaper notebook PCs also usethese cylindrical batteries. They are easy to buy but you need a spot welder to make the packs, Soldering or spring clips do not work Some high-end equipment does use custom batteries made in a space to fit the space, Apple does this in their Macs but mostly replacment cells will just drop in like C size cells, if you have a spot welder. For Lipo the nominal voltage is 3.7 per cell. Howerev that can be at 4.2 when fully charged and 3.0 when completely dead. Never dischange then below 3.5 volts or you can shorten the life of the cell dramatically. So a 3-cell battery is a goo replacement for a Lead Acid as the 3-cell pipo will range for 12.6 to 10.5 A fully changed 4-cell (at 16.8 volts might damage equipment designed for 12V LA. I've build a lot of stuff that uses LiPo and the best solution, the OLNLY way to go is to design-in a monitoring system. Human operators will destroy any LiPo battery quickly. But computers are good at this kind of thing. > A 13.8v LA charger was easier to make out of a spare plugpack than would > be a Li-Ion charger. Might have to snoop fleabay. > > Erik > > ¹ The ones which flew in the air, spewing flame and smoke, in one EV > battery pack repurposing I saw on youtube. > > > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users > -- Chris Albertson Redondo Beach, California _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
