2005 Prius to Light Duty Pickup Truck Conversion

Yes, that's why I took the approach I did, starting with a four accident Prius I bought for a song at HampaHybrids in Lutz Florida. He repairs and rebalances Hybrid Batteries and had used the car as a test mule. I figured I would attempt the modification first, and if that was too hard then I could always recoup my money by selling high value parts such as the inverter/converter and ECUs. I bought it without the hybrid battery because I figured the mod would take more time than would be healthy for a hybrid battery to sit idle. As it was, it took 5 1/5 months. Then, after the whole thing seemed to be plausible and I had worked out solutions, I started to deal with the basic car appearance issues. I have had several people tell me it startled them because it looks like it came from the dealership. Some others asked me where I bought it !!!!!!

No, i'm not in good shape because that's the configuration in which I get high temperatures. I just finished a prototype duct leading AC air from under the pax seat into the blower box and I will test that out before I make it a permanent installation. But of course you are right, I need to have sufficient suction air cross-section area so that the blower can pull air even if the AC is not on (unlikely where I live !!)

 

Since my original post about battery temperatures, I have established a "worst case" scenario about HB battery temperatures after exposing the Pruck to sunshine for several hours in the afternoon. Cooling air goes in at the top. and exits at the bottom. Worst case I have seen s 120 DegF at the top, 104 DegF at the bottom sensors. And these are not really the "dog days of summer" in Florida. My guess is that I need to do something creative soon so I don"t cook my HV battery. Today I created a duct manifold that will push cold A/C air from a duct under the pax seat into the blower compartment. I will test it out tomorrow.

 

And that is what I'll do. First, insulated the battery assembly from radiant heat from the black Line-X coated truckbed. I am also doing the floor AC duct modification since it is so simple to implement, and there are no back seat passengers any more anyway. That way, if the battery temps get too high, I can give it forced AC air. I used it today and never had a lower battery temp sensor reading higher than 98 DegF even after 1 hour in the Home Depot parking lot. But I am beginning to think that battery insulation against radiant heat from the truckbed surface is probably the most effective. I'll do some tests and advise.....R

Here's my update: I replaced the round grille shown in the previous pics (many times) with a new one which captures the AC floor outlet from under the passenger seat, as well as allow conditioned cabin air in (see picture, passenger seat removed). I partially plugged the remaining 3 AC floor outlets, but even then, the floor AC output is not much, however the duct feels very cold to the touch. I have also placed a 1" slab of "foamular" on top of the HB casing to combat heat reflection from the truckbed. Driving around from 9 am to 4pm in bright sunshine, outside temp 91 degrF, sometimes parked, sometimes city stop-and-go, sometimes Interstate, the lower battery sensor(s) registered average temps between 102 and 104, highest observed was 107 degF. Been thinking about making a insulating foam mold for the HB but I am not sure if I will be creating a hazard due to trapp d Hydrogen gases. Any opinions/advice ??....Ruud

 

Thanx Todd for your complimentary comments. Today I implemented fix #2, which consists of a 1.5" thick foam insulation jacket over the Hybrid Battery case, top, front, and back. Had to leave the ends open for access to the service plug etc. Hopefully this will combat/counteract the heat radiation from the black truck bed. This weekend will include a trip to northern Florida to attend graduation ceremonies, and I'll see firsthand the effect of battery case heat insulation, as well as the effects of the forced AC air into the blower compartment, which I can control/modulate. So I will report back again, recording data on my Scangauge II after I (we) return,

 

It's been a while since I posted. The Pruck (Prius pickup truck) is doing fine, has won an award in a local car and truck show, and has been in the local newspaper (TampabayTimes.com), on ABC Action News, and in an article in the "Hardworking Truck" magazine.

The hybrid battery heat problem lingers, especially since it is now brutally hot in Florida. It is OK if I move it out of the garage and then just keep moving/driving, and the lower battery temperature will usually stabilize between 104 and 107 Degrees F. The problem starts when it has been parked in direct sunlight for more than 2 or 3 hours. After that, the truckbed is literally too hot to touch, and the battery lies just 1.5" below that surface. Once moving again, the temp will go to 120 or 122 degrees F, which is within limits but as far as I am concerned, too hot for comfort. I can accelerate the cooling by manipulating the air conditioner but it takes a while for that to take effect. There are other things in the mill. But basically the car/truck is fine and fully functional.

Hybrid battery (cell) temperature is basically a compromise. Cell charge/discharge capacity increases with temperature, but cell life decreases with increases in operating temperatures. So I would like to opt for increased life.........Ruud

 

Yes, I've thought about that, but that would look a little silly and get dirty very fast. An alternative solution along the same line would be a tonneau cover. I'm still working on this problem. Thanx for you suggestion.

 

Incidentally, I am delinquent in providing PriusChat readers with the latest on the "Pruck", the light duty pickup truck conversion. So here are some links to recent media exposure. For those who would also view the TampaBay Times video, I offer that the audio is not properly synchronized with the video, leading to confusion as to what the H* I am talking about.....

What do you call a Prius hybrid combined with a pickup? The Pruck (w/video) | Tampa Bay Times

Florida engineer creates Prius truck | Medium Duty Work Truck Info

St. Petersburg man transforms Prius car into his own truck, the Pruck - Story | abcactionnews.com | Tampa Bay News, Weather, Sports, Things To Do | WFTS-TV

 

Thank you. I understand that Toyota may finally produce their small hybrid pickup truck (called the A-BAT) in 2017. They have had a prototype since 2008. We'll see.....

 

I would be remiss if I didn't announce that the "Pruck" finally has a tailgate - long overdue. Line with X-Line and painted to match the vehicle.