Converting to a PEHV.
http://www.a123systems.com/hymotion/

http://www.3prongpower.com/index.html

I'm sure there are more but these are all I could find. Just wondering if anyone has attempted this yet and if so how is it working out? Rick

 

Those are both for the prius. I have never seen a battery upgrade available for the camry.

 

The Camry was not designed from the ground up as a hybrid but is a modified version of the stock, ICE only car. The Prius that these conversions are used on was designed from the start as a hybrid and has several things working for it that help. The battery placement, hatch design and interior layout all help to make the conversion fairly easy to do. I don't know of any similar conversion to a plug-in for the Camry. If there is a project in the works, I would think the trunk pace is just about gone to be able to house the increased battery packs that would be required for the heavier car.

 

Nor have I, but like Rick I would certainly be interested.

I would like to hear from GH members: Who would be interested in a PHEV conversion for their TCH presuming:

1. It would charge from common 110 v 15A circuit in a few hours.

2. It would allow a forced EV mode.

3. It would have significantly more EV range than the stock TCH although not as much as do the Prius conversions.

4. The auxiliary battery pack would take some trunk space, but possibly not as much space as is taken by the Prius conversions, and the aux battery pack might be removable for long trips when more trunk space is required.

5. The conversion would not affect warranty.

6. On your typical drive, it might double your typical gas mileage.

 

I understand that most conversion are designed for the Prius. Yes I agree probably because it was designed as a hybrid right from the beginning. But some of these conversions are also applicable to the Ford Escape Hybrid, which like the Camry, was not originally designed as a hybrid. Also from what I've read, I don't think these conversions to the Prius change anything under the hood, it's all about the batteries. I just figured sooner or later someone would have come up with some sort of a way to extend the range ability of a Camry.

 

2. Prius has forced EV mode button, TCH doesn't. That button is disabled on US models due to 150k battery warranty, but it could be reactivated. Since TCH doesn't have anything like that, it would be much more difficult to build such capability, probably would require some computer programing.
4. That battery should be rather heavy, don't remember exact numbers, but wouldn't be surprised if it was over 100pounds, not easy to take out. Also there is a problem of 240 V wire and the plug dangling around. Normally you would have male and female plugs, with male usually without power when disconnected, in this particular case both connectors would have voltage at all times, kind of dangerous.
5. Forced EV mode would definitely invalidate the extended warranty on battery due to the fact that the battery could be discharged bellow recommended minimum.
6. what's typical drive? Standard battery is good for about 1-2 miles in EV mode. Doubling the capacity would most likely extend it to 2-4 miles, add another 2-3 miles for deeper discharge cycle, but that's about it. After you run out of extra juice, the car should have similar mpg as factory, there is not much benefit in having extra battery capacity, as documented when battery gets older, it looses capacity but mpg stays similar, therefore it should be similar the other way. So to double the mpg (around 80mpg ) you would have to drive mostly on EV power, I would guess anything above 10 mile drive would sharply lower your mpg.
I don't think this project is worth the trouble especially with gas prices where they're now. With just about every company announcing new electric/hybrid models almost every week (last I heard Porsche is building hybrid for the racetrack and Nissan coming out with new designs as well, not to mention Mercedes etc.) probably safer bet would be to look at new vehicles with range/mpg more suited to your particular needs?
IMO TCH still has one of the best balance of comfort/size, practicality and mpg at the moment.

 

Thanks to Rick and Peter for the replies.

I think their answers are :

Yes from Rick, and
No from Peter (plus a suggestion to reconsider the expectations in the question.)

 

2 - The whole point of adding additional batteries is to get more time in EV only mode, without that mode available, it's not really all that useful on a TCH

4- Battery size and weight and cost would depend on battery type. lead acid being the heaviest/largest/cheapest, lithium being the smallest/lightest/most expensive.

4a- Any additional batteries added would have to be isolated through a diode bridge anyway since they would likely NOT be the same NiMH type already in the car. This would prevent the end left in the trunk from being "hot" when the extra battery was unplugged. Good design would also not directly connect the plug to the batteries but rather through a control circuit of some type, which would enable the plug after it was connected to the main pack.

5- Forced EV mode doesn't normally drain the batteries lower the 10%, it just doesnt turn on the ICE to charge them right away, it waits til they are at the minimum to start the ICE. The pack extended made by Hymotion does not void the prius warranty, but you will probably get some nasty comments from your dealer if they ever see it connected.

6- useful range is very subjective, and varies by user. I have a 6 mile drive from my front door to the edge of civilization (first gas station), and greater distance for the grocery store, work etc. Ideally I would like to run to the store on battery alone but that would be a 20 mile range, and LOTS of extra batteries.

 

For reference, I thought I would add some details on how the Hymotion pack interfaces with the Prius.

Adding additional batteries is far for complicated the jsut plugging in extra batteries.

1- the pack has it's own charger, and must be plugged in to charge it. The pack can not charge from the cars brake regen.

2- the Hymotion pack works by adding current to the wire from the main pack to the inverter. The Hymotion pack is more or less in parallel to the main pack, and responds to the same commands from the hybrid system. The Hymotion pack never actually charges the main batteries. The car believes the main pack is always fully charged until the Hymotion pack is discharged, then the hymotion pack turns itself off and the Prius goes on with it's main battery as it did before. Any regen goes only to the main pack like usual.

3- There are very elaborate safety procedures implemented in the main battery pack that any additional pack must emulate. ie when the car is first turned on the computer verifies that the crash lockout safety is working by telling the main pack to turn off and back on in a very specific time period. Any additional batteries must respond at exactly the same time or the hybrid system will fault and fail to start up.

 

I was hoping to hear level of interest in such a PEHV TCH conversion ASSUMING it were possible, but we seem to have become bogged down in discussing the likelihood of my assumptions being achievable.

That said, the discussion, so far, has beeen useful in causing me to realize that the removable aux battery would require at least a hoist and would probably be impractical and unsafe for consumer use.

I remain, however, convinced that the other assumptions are technically feasible, if not today, then in the near future.

So, taking "4." (the removable battery) off of the table and suspending all other disbelief, for the moment, would anyone be interested in a TCH PEHV conversion with the remaining four assumptions?