2nd Gen Prius PHEV Conversion (Enginer plug-in lithium ion battery kit)

[bennelson]

Once the kit is installed (bolted in to the car) you can no longer access the spare tire area.

Some other conversion kits take advantage of the tire well space, by having some of the electronics or batteries down in that area.

As an alternative, I have also seen installations with gas lifts that allow a battery tray to flip up, so you can still access the tire.
Jerry Asher's "Spirit of DC" PHEV Prius uses lead-acid batteries in a flip up tray. I thought that was a nice design.

[bennelson]

EDIT:
Here now is all four sections of the video of us installing the kit.

http://www.youtube.com/watch?v=Kfy6O9TY9CM

http://www.youtube.com/watch?v=hydBumVKO2w

http://www.youtube.com/watch?v=hqXRkfu9hQo

http://www.youtube.com/watch?v=-Z6Joz2kXM8

[NeilBlanchard]

Hi,

I have a basic question: do the new batteries work in parallel with the stock batteries, to drive the electric motor? And does the car charge the new batteries at all; like during regeneration, or with the onboard generator?

[bennelson]

The plug-in battery pack is only 48 volt, significantly LESS than the Prius main battery pack.

The plug-in pack is charged at night. When you run the car, the 48V pack runs through a DC to DC converter to upconvert the voltage to just a little higher than the Prius OEM battery pack - in effect, the lower voltage pack acts as a charger for the high-voltage pack.

By always having the Prius battery pack at a higher voltage, the car uses the electric motor more, and the gas engine less, improving fuel economy.

Since they are at different voltages, and different battery chemistries, regenerative braking cannot recharge the plug-in pack.

On the other hand, by using only a 48V system, cost of parts are greatly reduced, and this is the most affordable PHEV kit available.

[ericbecky]

Ben,
When you test fit the battery box one thing I like to do is "smooth out" the black strips of stuff that is in the trunk area. Sometimes they are a bit uneven.

Also if you have a smart key, the sensor is back there and one option is to unbolt it, cut off the bolt and grind the bolt down. Then secure the sensor nearby with zip ties.

[bennelson]

All four of the videos are now uploaded and can be viewed a few posts back up the thread from this one.

[NeilBlanchard]

Hi Ben (or Tim),

Another basic question then: can the Enginer plug-in kit be used in place of the stock battery? In other words, if the stock battery was old and failing, could you just buy an Enginer kit (or similar) instead of buying a replacement stock battery?

Since it sounds like the DC to DC converter is a "one way" connection, even if you could use the Enginer without the stock bettery -- you could not then have any regenerative braking. :-(

And now, my curiosity is peaked: do any of the other plug-in battery kits use high voltage packs that run in "direct" parallel to (or completely replace) the stock battery?

[mrbigh]

Originally Posted by NeilBlanchard

Hi Ben (or Tim),

Another basic question then: can the Enginer plug-in kit be used in place of the stock battery? In other words, if the stock battery was old and failing, could you just buy an Enginer kit (or similar) instead of buying a replacement stock battery?

Since it sounds like the DC to DC converter is a "one way" connection, even if you could use the Enginer without the stock bettery -- you could not then have any regenerative braking. :-(

And now, my curiosity is peaked: do any of the other plug-in battery kits use high voltage packs that run in "direct" parallel to (or completely replace) the stock battery?

I'm sorry to jump in with some insights for your querries.
Answer to your first question is :...............NO
Regenerative braking works with or with out any type of batteries, but if you have non, Where are going to store that extra energy being recaptured ?
For your last inquire, for seriuos PHEV available equipment, not as primitive as the Enginer KIT, the options are Hybrid Interfaces and the not so cheap PICC. These ones will replace or augment the original capacity of the NiMH battery pack to attain a larger range in PURE EV mode and with FULL regen capabilities

[NeilBlanchard]

Thanks for answering my questions. On the regen question: I meant to say that you cannot capture any of the regenerative braking with the Enginer battery (because the DC to DC converter only works in one direction). So without the stock battery, all the braking energy ends up as heat only; whether it is regenerative or friction.

I will take a look at the other companies you've mentioned.

[bennelson]

There is at least one converter that I know of who will completely remove your battery pack and replace it with a much larger battery pack, but we are talking like $40,000 or something rediculous like that. The upside is that you have a much bigger back that you can regen to.

This PHEV kit is really not designed to be able to directly drive the car. I just constantly supplements the available power in the main battery pack, constantly adding some power to it.