Make a Gen III a plug-in?

Some information to review for G3 kits... top speed is something to look at.

http://www.pluginsupply.com/
Toyota Prius 4 kWh $5,500
Toyota Prius 10 kWh $10,995

http://www.enginer.us/products/conversion_kit.php

PHEV 2KWH Kit for $1,995.00
PHEV 4KWH Kit for $3,495.00
PHEV 8KWH Kit for $5,495.00

http://www.enginer.us/img/Enginer%20PHEV%20User%20Manual%20Generation%203%20Prius.pdf

Plug-In Supply
Toyota Prius 4 kWh $5,500
Toyota Prius 10 kWh $10,995

 

So which is better? The pluginsupply unit is a lot more money, is it a lot better product? How big of a kit is needed?

 

There aren't many PIS users in this forum. All of them are Gen II users and are of older system. I think it's because of the cost.

There are many Enginer users in this forum. A lot of them are Gen III users. A couple of things that plague the Enginer kit are the BMS and the converter. The supplied BMS doesn't manage the batteries very well. It ends up damaging the batteries. There are couple of aftermarket BMSes that will work with the Enginer kit, MiniBMS-Centralized and PacificEV BMS. The latter is designed specifically for the Enginer kit. MiniBMS is a universal BMS that can be wired and modified to work with Enginer kit. I have the MiniBMS and so far it's been working well. One down side to the PEVBMS is it cycles the charger on and off once the battery is fully charged to top balance the battery. This can be good if your battery is out of balance. It can be bad to the high cell constantly being topped off. The soul of the Enginer kit is the converter. It basically works like a step up converter. It converts 48V input to 240V output. Simple enough but it's not. The downside is the converter is not reliable. It over heats and shuts off if used for a long time. Eventually it'll burn out. Warranty is also a bitch because the turn around time can take months.

There is no support forum for Plugin Supply kits so we don't know what kind of reliability it has. I've seen the kit in person and it's a well designed kit. It uses 76 LiFePo4 cells wired parallel to the traction battery via contactors. There's a piggy back ECU that communicates with the stock ECU to allow more electric assist. The electric acceleration is much peppier with PIS kit than Enginer kit. Enginer kit does not modify the ECU in any way so in order for you to accelerate in EV only, you cannot press the gas pedal pass the half way point of the HSI bar just like the stock Prius.

Judging from your driving habit, both kit will work. If cost is an issue, I'd go with Enginer kit. However, I would recommend the PIS kit due to much more electric assist than the Enginer kit. With such short distance, You shouldn't have any reliability issues with the Enginer kit. One more thing about the Enginer kit. Its cooling fans are loud as hell.

If you decide to go with Enginer kit, you'll also have to do either a temperature hack to bypass the engine warm up cycle http://priuschat.com/forums/gen-iii...s/76906-yet-another-thermistor-hack-gen3.html or an EFI hack to disable the ICE completely . In both cases, you need to purchase a Scangauge II to either monitor the engine temperature or to clear warning lights codes.

There are so many Enginer kits in the wild, you can probably find a used one for way less than $3,000.

 

Another obscure but in this situation effictive option would be a BMS+ and a couple extra battery packs. I have always liked the "geniusness" of the system but was dissapointed that the support for the system never got developed. There is some discussions of it in the Gen II PHEV Plug-In Modification section.

 

+1

After all these years of producing these kits why can't they have improved the ease of having one? Selling a trouble free kit would increase sales 10 fold or more.

 

plugin conversion doesn't invent itself. Someone has to research it. Someone has to iron out the bugs. It costs a lot of money to do it. No one wants to fork out their own money to do the research. You can't just strap 4 KW batteries to the HV power line and call it a day. The stock ECU's gonna know somethings wrong and light up the dashboard like x-mas lights. I want a system that's trouble free too.

 

Gen 3 makes a great plug-in candidate. They share the Gen 2 drive system, there are kits as mentioned above for this system.
My company, ConVerdant, has installed both for NewEngland customers. There are differences is in function and reliability. Both kits offer some EV mode capability, and both can be over-riden by Toyota's ecu.
In my experience, the Enginer kit has needed some shop visits so I recommend this kit where the owner is a competent tinkerer or where the installer is within easy commute. It is a good kit at a great price that can hold EV mode [mostly] up to 34mph. The Plug-in Supply kit is a better kit that rarely needs shop visits, but at a higher price. It holds EV mode up to 70mph and does an even better job of sticking in EV mode. For cold starts in winter, there is no absolute solution for EV mode, but the PSI kit is stickier.