Charging HV Battery to MFD full SOC

[Presto]

I can't believe I didn't know about this feature before, but it may interest folks who live in flatter areas that never see the SOC go to the green bars. After having a discussion with my friend, he told me that I should be able to charge the HV to a full SOC (green bars) without regen braking down a long hill.

1) Put the car in D (drive)
2) Fully press down the brake pedal
3) Press down gas pedal (the further you push it, the greater the charge rate)


The car will charge at a max rate of ~60 amps. Once it starts to reach full SOC then it will not charge as quick. It sucks down the gas, but it's a good way to get a green SOC. The Prius never ceases to amaze me

[Tideland Prius]

Yeah but I don't like idling hehe. Besides, Vancouver's hilly enough.

[Ray Moore]

We did this prior to running the 1/4 mile at the Houston raceway. The only problem is that it heats up the inverter and battery so some of what you gain, you lose back to increased resistance from heat in the components. We tried to let it rest prior to the run but of course you want the engine warm. I'm not sure what the best balance is for achieving the fastest times. I'm sure a can-view would help but for some odd reason, I don't have one yet. Our fastest time was 17.8 seconds at 87.7 mph.

[Presto]

I ran into a similar problem with the HV battery getting too hot after a full charge to be useful under immediate hard acceleration. I'm wondering if there is a method to cool the battery quicker, like running the a/c directly into the battery vent.

[Frank Hudon]

the problem comes in from the internal cell temp. We have the same problem with forklift batterys with the middle cells of the battery boiling at the end of an extended charge. Ideal is 8 hours charge followed by 8 hours of cooling and then 8 hours of use. It's the internal temp that is slow to drop to a temp that leaves the battery in it's most effecient state.

[Amyshubby]

<div class='quotetop'>QUOTE(Presto @ Apr 15 2006, 11:41 PM) [snapback]240389[/snapback]</div>

I can't believe I didn't know about this feature before, but it may interest folks who live in flatter areas that never see the SOC go to the green bars.[/b]

I live on Long Island. It's a long flat island. Interestingly, my car usually has either the green bars or is one bar below. I see the green bars on almost every trip.

[cwerdna]

[quote=Ray Moore @ Apr 16 2006, 10:25 AM) [snapback]240522[/snapback]</div>

We did this prior to running the 1/4 mile at the Houston raceway.
...
Our fastest time was 17.8 seconds at 87.7 mph.
[/b]

You sure your trap speed was 87.7? That sounds awfully high for doing a 17.8 in the 1/4 esp. given how little power the Prius has. I could believe 78.8 mph.

My best 1/4 mile on my 02 255 hp Nissan Maxima was 14.908] 94.32 mph.

A quick skim of some econobox times in a recent Car and Driver shows times in the 16.7-17.4 w/the highest trap speed being 82 mph (17.0 at 82 mph and 17.4 at 82 mph)

[Presto]

I think what contributes to the Prius' time is the quicker-than-average acceleration thanks to the high torque of the electric motor, and the lack of having to shift with the CVT.

[cwerdna]

[quote=Presto @ Apr 16 2006, 06:34 PM) [snapback]240673[/snapback]</div>

I think what contributes to the Prius' time is the quicker-than-average acceleration thanks to the high torque of the electric motor, and the lack of having to shift with the CVT.
[/b]

High torque doesn't help that much w/drag races judging by 1/4 mile times of say the Nissan 350Z vs. the Mazda RX-8 and Honda S2000 (those have fairly high hp but low torque).

At http://www.caranddriver.com/article.asp?se...1&page_number=4 [page isn't working right now, cached copy is at
http://72.14.203.104/search?q=cache:A2bYrj...lient=firefox-a they got a more believable 18.3] 76 mph.

[hobbit]

Question is, how did you launch? You'd probably do best having
the ICE already running, in "B", and have the accelerator slightly
pressed so that the instant your left foot comes off the brake,
all that lovely combined torque is right there. Wasteful as hell,
but probably what you want for the quarter.
.
_H*