Hymotion & Emergency UPS

Yesterday, I got the opportunity to test the Hymotion battery as a supply for electricity. I lost power at my small computer office which hosts web sites and emails. Power was out about hour and fifteen minutes.

I used an AIMS 10 AMP pure sign wave inverter hooked to the 12 volt battery. I placed the Prius in Ready mode and hooked up the inverter. It supplied about 75 amps at 12 v or 7.5 amps at 120v. I've used the inverter before and the stock battery would drain and the car would run for a few minutes. It was interesting with the Hymotion battery the system ran for 45 minutes without starting the car. In fact, I noticed the Hymotion battery pack was only down 1 bar when the electricity came back on. My calculation show I could have used the arrangement for a few hours before Hymotion was depleted.

It's too bad that Hymotion locked out the charging capability when the car is engaged. Even if the Hymotion is in the off position, no charging can be accomplished. It would have been nice after draining the Hymotion battery on long trips to be able to put back some charge while driving.

---Kent

Sounds like you have a good backup power source now. Sounds like I might have to turn my Prius into a UPS.

I tried to turn my Prius into a UPS, but it wouldn't fit under the computer desk.

Tom

Yes, I was very pleased with the results. You can pick up a 10 Amp inverter at a reasonable cost. I purchased the pure sign wave, since I was using it for computer equipment and phone systems. That added to the cost, but with 15 minutes of the power going out, we had customers calling to find out why their web sites and email were not working. Very worthwhile for my situation.

---Kent

Out of interest, would it be easier to implement a high power DC/DC converter setup for this purpose? There'd be less energy wastage going from approx. 240V DC to 110V AC (or 230V AC in Europe) than from 240 - 12 - 110? Also, what's the maximum power for the 12v circuit without trouble?

Great work though. I'm really pleased that this experiment was a success. The next thing I'd want from such a project would be a way to inhibit the car from driving away. I have two 16A charging ports on the outside of my house. It'd be quite easy to turn the Prius into a UPS if an approrpiate switcher was made but I'd not want the car to be left outside with the ignition active!

Ideas?

Nikki.

Easier no, more efficient absolutely. I pulled two cables off the battery straight to the inverter.

I now made a male to male 110 v cable. I'm going to mark the breakers to turn off everything except to the office. No extension cords just turn off the main power until it comes back on. I'll plug the car into an outlet in the garage with it powered to the office only. Car will be safely in the garage with garage door opened to avoid fumes.

---Kent

Cut in a secret switch for the brake light lead, then someone
can't get in and put the car in gear without knowing the trick.
.
_H*

Build a dummy and place it in the drivers seat. Dress it like a Raiders Fan, (strategically dressed like a hairy Latino), then nobody will get near the car, even with the garage door open...doh