Modify Prius C software

If you're looking to do 10 miles of EV driving, a PiP or other PHEV is the best way to go.

Look at the grid chargers people make for the Honda Insight and Civic Hybrids for ideas. You'll probably need to adjust the max voltage to the C's max. Maintenance charging periodically isn't a bad idea. However, you probably don't need one. The Prius tries to leave some extra space in the battery for regen. Unless you're going down a large hill, its pretty normal for it to not get charged all the way. I'm not sure how it is in the C, but my Gen2 will "actively" charge the battery to 6 out of 8 bars and try to maintain it about there. I don't think I've ever seen it get to 7 or 8 bars without going downhill.

Turning your Prius into a PHEV using just the stock battery is a pretty sure way to drastically reduce the battery's life expectancy. The car only uses about the 40% to 80% charge range (again, this is for the Gen2, may be a little different for the C) of the battery in order to make it last for years. This is range is scaled to the battery charge indicator, so 0 bars is actually ~40% and full is ~80%. Also, charging the battery at 30A would be unecessary if the car is going to be plugged in most of the day. The pack is only ~7Ah and should be at least 50% full most of the time. That 7Ah brings us to how small a non-PHEV Prius' battery really is. Multiplying that by the 144v of the C's battery pack gives you about 1kwh if you go from 100% all the way to empty. Most EVs average around 300wh per mile, so at best that would give you 3 miles of EV.

 

You be better off trading it in for a volt! Way in the cost of convertions voided warranty, hardly worth it!

 

Take a look at the Enginer PHEV kits for the regular Prius. A setup like that would probably be the easiest route to go (other than buying a PHEV). They might even be able to work with the C, I believe the DC-DC converter's output voltage was adjustable.

 

try pis for a (turnkey?) solution but expensive. iirc, there may be a thread here from a guy building a larger battery for the c, try searching. not sure he ever finished though. the best thing you can do is buy all the schematics and study what others have done on the hardware and software side on the lift back. some very intelligent people have made a go of it, but it's not easy.

 

A means to force EV mode when I want sounds like an awesome idea. It would be useful if I'm only moving my car from one parking spot to another, or if I want to restrict acceleration to only using the battery. I wish it was a normal option. Regarding 6MPH, highest speed I've ever maintained and still remained in EV was 42MPH. I found that if I was too aggressive on the accelerator I would drop out of EV immediately.

 

i hope 'low speed ev anytime' is on all the new hybrids.

 

It's not on the 2015 C anyway. It's not on my 2013 Camry hybrid either.
I don't know why Toyota isn't giving us low speed EV either. At least moving without the "gas" pedal should be allowed for moving the car around the driveway/parking lot.

 

absolutely.

 

It would be better to have 2 different chargers.
The trickle charger is easy to make. Parts would be less than $100. Basically buy some led drivers and wire them in series. Add a fuse and other safeties. I have shared plans in the past.

Making a 30amp charger could be a bit challenging. Do you just want to use it at home? Buying one might be pricey. How much are you looking to spend.

Lastly, I haven't researched much about adding EV mode. How about making an out of gas more instead?

 

I am not sure if this directly addresses your topic, but I do know that the computer intentionally keeps the battery from about 30% to about 60% charged, because shallow cycles make it last longer.

 

Actually the charge is maintained very closely between 40 and 80%.
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