As I plug in the unit for my rechargable AA batteries, I began to wonder if anyone has tried to max out the charge on thier hybrid batteries by plugging it into the house electrical outlet?

There are several companies modifying hybrids into plug-in hybrids (PHEVs). You can google that and get a ton of info. Generally they take the existing system, add 3-5x the battery capacity and a 120VAC charging system to allow about 10 miles of electric-only driving (as opposed to 2ish miles on the existing batteries) after an overnight charge. The rest of the system operates normally- regen, etc.

try here as a start point: http://www.evworld.com/

As for doing it in your garage, it would take significant EE knowhow and time/willingness to monkey. An entirely separate transformer and charging system are required.

Keep in mind if you charge at home you are trading gas power for coal power because most electricity come from coal.

There are complicated ways to achieve this in Prius. Bear in mind that they may affect the longevity of your battery if you raise it to 100% state of charge, and *will* affect longevity if you allow the battery to overheat during charging. Plus, electrocution can be unpleasant.

There is a simple way: fully depress brake pedal, shift to R or D, now also fully depress accelerator pedal. This consumes gasoline. It will stay within the battery management system's safety parameters (ca. 80% SOC, ventilation fans on ca 40 oC, etc.). Only useful as a curiosity (watch the battery bar climb), drag racing, or similar. So, why bother? Informal Prius term "force-charging".

DAS

I guess it depends on where you're getting your electricty from. This graph was labeled annual date for 2004. In my quick yahoo search I also saw some search listings that said coal was around 51%.



http://www.eia.doe.gov/cneaf/electri...pa/figes2.html

I've found myself wishing that I could "top off" my battery pack overnight. After a commute both ways of trying to P&G, my pack is sometimes down. When this happens and it's cold the next morning, I find I get forced regen on and off for the first few miles until the battery indicator gains another bar, and the batteries warm up, I assume. ICE doing the regen while it's cold - ugh! If I could just plug it in to give the battery pack a little boost I think I'd save fuel and pollution.

The ICE will run no matter what until the catalytic is up to temp for emissions requirements, so the savings is probably not so much.

To back up what Tochatihi said, the packs are maintatined within tight levels, something like 30-70% or something to minimize adverse effects caused by completely charging or discharging the batteries (I'm not a battery chemistry expert, so I can't quote specifics). The closer they can be kept at a constant energy level, the longer lifetime they will have. Charging above what the controller normally allows might be possible but has a good chance of being penny-wise but pound foolish.

It might be very worthwhile to look into the emerging PHEV options, though.

Thanks, Bryan.
Yeah, I understand. I wouldn't want to top it off to more than what is good for the battery. Let's assume the 30%-70% range is correct - it doesn't matter, it all translates to "bars" on the battery gauge. If mine is down to the minimum number of bars that the system will let it go to, I think it's like four or five bars, when I park it at night, and I start driving in the morning when the batteries are cold, I will get an almost constant forced charge unless I'm accelerating. I suspect what's happening is the batteries have lost efficiency because they are cold, so they drop below the minimum charge. This forces the ICE to charge them to protect them. Adding some charge overnight should keep this from happening (or pre-heating the batteries somehow). Of course it's a moot point, since there is no A.C. recharge option.