[rbgrn]

Does anyone have experience converting a Prius to a Plug-In Hybrid? I'm interested in buying one but I'd like to know how to add a little range and go the plug-in hybrid route.

[summer09]

i havent heard anyone converting a hybrid car into a plug-in hybrid... better buy a plug-car if i were you but it's still rare to see one for now...

[oldtimer]

There are no range limits on a Prius, its a hybrid. Mileage does jump with the plugin conversion, I've read. There are a couple of companies offering conversion kits that I've seen listed at Priuschat.com.

[rbgrn]

I meant pure EV range.

[oldtimer]

There actually isn't a "pure EV range", however if you keep your speed under 35 and are very careful with your driving techniques you can keep it mainly in electric without having the ICE kick in . I'm not sure if the conversion kits allow for pure electric mode, although Toyota was supposedly looking at being able to keep it in electric mode for first 40 miles when they were planning to add PHEV in 2010 model, now postponed until new batteries are available. Hypermilers in recent contests were actually reaching 200+ mpg on standard Prius hybrids.

[rbgrn]

What I initially was asking about was a mod to put it into EV-only mode until the batteries were drained, then running off the ICE to drive and recharge. I heard the japanese ones have an EV button that does that but it wasn't put on the US models.

[grose]

Originally Posted by rbgrn

What I initially was asking about was a mod to put it into EV-only mode until the batteries were drained, then running off the ICE to drive and recharge. I heard the japanese ones have an EV button that does that but it wasn't put on the US models.

I've heard about that EV button too, but it was for cars going to Europe. As of right now, I think there are only a few companies doing plug-in conversions. They add an additional battery and tweak it to stay in EV mode longer (I think it was up to 35mi/hr) The cost for this was still high though. I don't think there is any "easy" mods you can do yourself.

[Rolls Kinardly]

The "EV button" can be added to any Prius. It is standard equipment on the Japanese models.

http://www.calcars.org/prius-evbutton-install.pdf

Any pushbutton switch will work, but you can buy the JDM EV button for a totally stock look.

The button basically tells the Prius to not bother warming up the engine like it normally does when you first start the car. It does not increase the speed at which the Prius fires the ICE. I believe that speed is 41 MPH. Toyota is or was testing a few PHEV Prii in California that could stay in EV mode up to about 60 MPH. It is unknown whether this required a hardware change or simply a software (ECM) tweak. Toyota of course won't say.

There are a few companies that sell PHEV systems. Hymotion (now owned by A123) is a big one. I have seen DIY jobs with gel cells as well. It isn't particularly complicated for someone with a DIY mentality.

I watched a Prius get converted last year. A high voltage/current connector (Anderson connector) is added where the stock battery connects. The additional battery is bolted into the cargo area. The EV button is added. Even without the EV button, the additional battery will improve mileage quite a bit because the Prius will use the electric more when the state of charge is high.

The relatively high cost of the battery (most use Lithium Ion) means the payback period is quite long. Of course this depends on the usage pattern.

If I am not mistaken, it is impossible to recharge the additional battery pack through Regenerative Braking, only from the grid. So if you expend the additional battery on a long trip, you're driving an ordinary Prius with a bunch of extra weight until you can plug in again.

There are a couple or three PHEV Honda Insights in existence, and at least a couple more in the works that I am aware of. The MIMA system is required to take full advantage of the additional battery capacity in the Insight.

[Rolls Kinardly]

Here's a 33 minute video of a Prius being converted to PHEV at the LA Auto Show last year. Felix Kramer, founder of CalCars (the first company to do a PHEV conversion of a Prius) speaks about the process. Interestingly, they use NiMH in this one.

http://www.pluginamerica.org/multime...auto-show.html

[oldtimer]

33 minutes? That's 50% more than the average person's attention span! LOL