charging milwaukee 18v tool batteries in prius

You can use the inverter to charge the Milwaukee batteries and still run the 12V refrigerator without any current issues, but you will have a battery capacity issue. The 12V battery on the Prius is fairly small, so it doesn't do well when used for extended loads. Also, the 12V receptacles on the Prius are switched: they will turn off with the car. You can rewire them if you wish, but keep the small battery in mind.

The alternative is to leave your Prius in Ready mode, where the large traction battery supplies electrical power and ICE can come on as needed to recharge it.

Tom

 

One simple solution is to just leave the car ON ("Ready"), in Park, with the parking brake set. Then the two charger outlets will be active and the car will keep the 12V battery fully charged. No modifications required. If necessary lock the car using the mechanical key stored inside the fob.

If a Solar charger works for your application then why not use it?

 

There is no "alternator" in the Prius. The 12 vdc side is handled by the Inverter/Converter. Some folks have turned their Prius into a UPS to power their home during a power blackout

PriUPS-getting electricity FROM your hybrid vehicle

The only caveat is that the 12 vdc battery is quite small, think motorcycle sized. I took this photo of my Prius battery after hooking up the VDC Battery Minder harness to it



The only way to power stuff with the Prius is to leave it in Ready. The gas motor will automatically start and stop to maintain correct charge in the primary NiMH battery pack, which powers the Inverter/Converter, which charges the 12 vdc battery and accessories

 

Uhh, true. Any rack will hurt MPGs.

What about leaving the car on? Does that not work in your situation?

Adding more batteries could be a problem if they ever all got significantly drained. The DC-DC converter is fused to 100A or so, and four depleted batteries might easily want to suck more than that when the car is turned on. To completely prevent that possibility you'd have to leave the car on whenever you were using the external 12V equipment... but if the car is going to be on anyway then you wouldn't need the extra batteries.

 

I'd be more worried about someone breaking in just to steal the laptop or those nice expensive tools. A Club won't prevent that. But yeah, if the car is on there's nothing to stop someone from breaking in and driving away.

 

I removed the trim panel to take the photo. A larger battery would have to be hooked up externally. Hobbit has had good writeups on this

http://www.techno-fandom.org/~hobbit/pix/prius-ferrups.jpg

Hope this helps

 

If your tool batteries are charged overnight outside the car, and you just use the Prius battery to maintain charge, maybe you'll be fine--extra batteries? But if you're re-charging in the car while it's off, and using the refrigerator 24x7, another solution may be needed.

I still plan to install a cigarette lighter socket under the cargo floor for a rechargeable lantern with its charger base. However, I also have the same lantern in the garage, and will use that base to charge the car lantern, and use the car to maintain charge. The charger says 500 mA on it, but the trickle charge to maintain the battery draws only 10mA. I'll run a power wire from under the dash via the driver-side door sills using the excellent instructions and photos by [FONT=&quot]Judgeless at my older thread:[/FONT][FONT=&quot] http://priuschat.com/forums/gen-iii-prius-accessories-modifications/72677-adding-12v-charger-led-[/FONT][FONT=&quot]lantern.html.[/FONT]
The manufacturer responded that it was OK to use a switched source, since the car is used every day.

 

Be careful Milwaukee tool chargers use roughly 300 watts each to charge. I ran into this in my work truck. They would blow the 20 amp fuse on the lighter outlet when using the inverter for them. Also the prius outlets are fused at 10 amps.
Solution... run a dedicated outlet and only run when the car is running.