Enginer PHEV Test Pilots: Mpg reports and important data

[docbooks]

Originally Posted by linuxpenguin

You're not being too dense, it's a good question =). I agree with MJFrog here--it really isn't apples to apples because yes, the Enginer system cannot push EV mode for 10+ miles in a row unless you drive extremely slow and stop every so often and let it recharge. Unless you seriously change your driving habits, this isn't really practical.

It's also not apples to apples because if you do end up depleting the OEM battery during EV mode (which you likely will unless you carefully monitor the SOC bars left and cut out at the right time) in the Enginer system, the ICE has to work twice as hard to charge up the OEM battery again /and/ propel the vehicle thus fuel is wasted charging the battery because the DC/DC converter can't keep up.

As for CGate's question about using the ICE to charge the battery, the ICE is terribly inefficient at those speeds (basically idling while the car is stopped and charging it at around 20 amps). Remember, the Prius internal combustion engine is only around 31% efficient--one of the best in its class no doubt, but still, 31% efficient. Most of the energy is burned off as heat and is lost. No, you're much better off charging the OEM battery either thru the DC/DC converter (takes a long time) or directly with another charger (dangerous!).

To answer your question again DocBooks about it being roughly the same--yes it /generally/ ends up being pretty close but it really depends on the conditions already spelled out =).

Andrew

Thanks for the response -- it sounds like all Toyota has to do is increase the size of the OEM battery by a factor of 2 or 3 ( and the corresponding increase in springs and shocks, etc) and then with the addition of the Enginer pack, we're getting pretty close to a true plug-in all EV for under 10 mile trips at low speed. I'll be keeping an eye on future posts for the great info therein.

[kiettyyyy]

So, time for another update.

Remember back during the Summer when I had a defective Enginer kit? Well, lets put it straight, 3 defective DC/DC converters. I was given 4 sets of the 12V LiFePo4 Thundersky batteries as a token of appreciation for helping out with the testing and development of the kit.

Well.. I've just been busy until last Thursday. I decided to throw the 4 sets(16 3.2v 40ah cells) into the spare tire area. These batteries are wired in parallel with the existing 4kwh Mottcell kit(Yes, I know the Mottcells are at 39AH, where as the Thunderskys sit at 40AH.. It doesn't really matter as long as you keep an eye on the voltages of the Mottcell cells).

I don't have any pictures.. but I'm just here to post the results:

Battery Chemistry: LiFePo4
Total WH: 6195.2 Watt/hrs
Charging time: ~6 hours
PHEV Range: ~75 Miles
My MPG Average for my 74 mile commute: 74 MPG

How does this compare with my Plug-in Supply kit(2008 from January to June)?

Battery Chemistry: Sealed Lead Acid
Total WH: 4800 Watt/hrs(2100 W/hr usable)
Charging time: ~4.5 hours
PHEV Range: ~25 Miles
My MPG Average for my 74 mile commute: 71 MPG(For first 3 months), 69 MPG(for the next 3)

Well, I'm finally satisfied with my results. 74 MPG for many years to come? We'll see what the results are in a few weeks...

[sub3marathonman]

This may have been answered somewhere else, but why would you get the Enginer kit if you already had the Plug-In Supply kit? Did something go wrong with it?

Also, what seems to be very interesting is that even with really just 2kwh of power from the Plug-In Supply kit you were getting almost the same milage as with now 6kwh of power from the Enginer kit. What was the milage with the Enginer kit when it was just the 2kwh kit?

[kiettyyyy]

Originally Posted by sub3marathonman

This may have been answered somewhere else, but why would you get the Enginer kit if you already had the Plug-In Supply kit? Did something go wrong with it?

Also, what seems to be very interesting is that even with really just 2kwh of power from the Plug-In Supply kit you were getting almost the same milage as with now 6kwh of power from the Enginer kit. What was the milage with the Enginer kit when it was just the 2kwh kit?

It was already answered in a previous thread, but, it's here anyway:

I didn't want to replace my lead acid batteries every so often.. Also, the kit was rediculously heavy(I even had the rear shocks upgraded, but it really impacted my vehicle's performace when accelerating up hills). I wanted to move to a lithium kit, but to do that with the Plug-in Supply kit, it would have cost me about 6k to do. Oh, the support wasn't so great either.. All of this made me switch to a LiFePo4 kit.

I wouldn't say it's 2 kwh of power. It's really 5, but Peukert's law really screws things up. When you charge the batteries, you really pull 5 kwh from the grid.

To put it into perspective, the Enginer kit works EXACTLY THE SAME/OUTPERFORMS as the Plug-in Supply kit on long range trips utilizing a highway.

To me, this is a deal breaker for the Plug-in Supply conversion and a deal maker for the Enginer conversion. I rarely do city driving as my commute to school is all highway at 60+ MPH speeds.

Oh, also, here's an additional MPG result:

My MPG Average for my 78 mile trip: 72.3 MPG

[kiettyyyy]

Well, I did some EVing today around town as I had no school due to the holiday

I fired up both converters the second I left my driveway and proceeded onto the rest of my trip. Well, half way through the trip, the red triangle of death triggered and I was booted out of "Ready" mode.

The DTC was: P0A90

I pulled over, rebooted the car and cleared the error code. Before I rebooted, my SOC was about 77%.. After I rebooted, the SOC was at 59%.

I cleared the code and went on my way in EV.

Any ideas what just happened? This is the FIRST time that I have ever received the error code while EVing..

Oh, I'm sure someone wants to see the MPG data:

I drove 21 miles in EV.. I had PLENTY of juice left for at least another 5-10 miles.

Max Speed: 44 MPH
Average Speed: 32 MPH

[Fibb222]

After 1 month of having the Enginer kit our average mileage improved from 50 mpg to 67 mpg or an increase of 34%. I think we can do better with more practice. It's too bad we have hills everywhere.

[docbooks]

Originally Posted by Fibb222

After 1 month of having the Enginer kit our average mileage improved from 50 mpg to 67 mpg or an increase of 34%. I think we can do better with more practice. It's too bad we have hills everywhere.

What size KV kit do you have?
Thanks

[Fibb222]

Originally Posted by docbooks

What size KV kit do you have?
Thanks

4kW like the ones being sold now.

[docbooks]

Originally Posted by Fibb222

4kW like the ones being sold now.

Sorry, meant KW -- did you install it yourself or have them do it? And do you think that the size you got is the best bang for the buck vs the 2 , 6 or 8 KW?
Thanks in advance
Jim

[Fibb222]

Originally Posted by docbooks

Sorry, meant KW -- did you install it yourself or have them do it? And do you think that the size you got is the best bang for the buck vs the 2 , 6 or 8 KW?
Thanks in advance
Jim

I should have said 4kWh. Anyway, I think the more cells the better the value, unless you don't drive very far each day of course. But I personally wouldn't go higher than 4kWh if that meant I would loose some trunk space above the carpet deck.