Enginer almost non-stop EV mode?

I wonder if this would help with temperature control of either the Prius HV battery or Enginer converter:
TEC1-12706 Finished Cooler Peltiers With Heatsink & Fan - eBay (item 160467220691 end time Nov-08-10 23:59:30 PST)

 

The Ewert "hack" somehow allows EV mode up to 52mph and ICE "coast" EV up to 70mph:

Apparently it's just something that can be done via CAN, no software changes needed to the Hybrid ECU. The only way to get this at present is in the PICC kit. They have not been willing to offer this without buying the full kit.

So I'm also working on this for my custom PHEV. I will definitely not be using the "ICE Kill" hack which I think is Dangerous. I works just by disabling the ICE, and then clearing the trouble codes. At that point you will have a full 52mph EV, However the ICE cannot be restarted without pulling over and re-cycling the power.

 

Not likely. Peltier coolers are not efficient. It would thousands of watts to cool the HV batteries and the enginer kit. Totally not worth it, a major hit on MPG. You're better off getting high CFM fans.

 

Bizarre. Great minds. I actually bought one of these a few months back for just this use. There are a few issues. First, to avoid the need for voltage conversion, you need to rewire the TECs to present a 48 volt load. They are all potted in place with foam, so it requires quite a bit of work. I damaged some of them taking them apart. The second issue is that you need a controller. I imagine that ebay has one that works on 48 volts if you hunt around. (I don't want to tap half the PHEV or 1/4 of it for the more common 24v or 12v as we have already seen what sort of cell imbalances are caused by simple things like powering the BMS display off a few of the cells or even drawing power for a CellLog.)

The third issue is that you have a huge water management issue. You'd need to find a place to put this beast where the condensation (in Miami it would be substantial--maybe a gallon or two a day) can drip down into a drain tray and then channeled outside the car.

I originally wanted the A/C unit to cool down the cabin at night in the summer where the nocturnal temperature was not dropping below 85oF. I figured if I could drop the system temp by another 15 degrees at night leaving me with a cooler starting point in the morning, I'd get another 10 or 20 minutes of operation before I overheated anything.

In the end, my Enginer system has been out of operation for most of the past two months and I have not had the energy to get into thermal management again. But, using some of the overclocking heat management solutions by Zalman or others based on forced convection and using heat pipes to move the heat is probably the soundest way to go and I will look at this. Fortunately, we are heading into winter where we expect the temperatures to get down into the 70s (hopefully) and the problem is deferred for another 5 months.

 

Well, I believe this unit itself is about 50% efficient and provides about 200W of cooling for 400W of input. I guestimated that 200W was sufficient to do something good. It's probably no worse of a solution than using the car's A/C due to all the conversion losses there, i.e. gas engine to alternator to electric compressor.

In the end, it was the other engineering concerns I've mentioned that finally made this thing not worth the time.

Certainly the forced convection solution is a cheaper more efficient way to do things. But, you can only do so much when you are using a fan to try and get things below 114oF and your baseline in the shade is 95oF or worse in the sun. In my case down here, I think that heat generation due to operational losses is much less of the problem than the huge thermal mass of the system not getting below 92oF even after being garaged overnight for 10 hours because it just never cools down at night here.

 

Also, another little quirk I noticed is related to the cruise control. I religiously use CC to keep the car operation as steady state as possible. The cruise control COULD be quite effective at keeping me at exactly 33 MPH. The problem is that in non-EV mode, the cruise control WILL engage at this speed. EV mode use PRECLUDES simultaneous cruise control use; however. I don't really understand Toyota's rationale on this one, but none the less it's there on my 2G....

 

Same on 3G, setting cruise control deactivates EV mode....

 

I can routinely drive the 2.8 miles (each way) to and from work entirely in EV mode. It was very difficult with the 3kW converter, which wasn't working correctly anyway, but now that I upgraded to the 5kW converter, I can do it easily.

The route is mostly flat. I take back roads where the speed limit is 30, and the part where the speed limit increases to 35 is 3 lanes in each direction, so I just go to the right lane and drivers will pass me.

The trickiest part is where the road crosses the railroad tracks. For that section, I have to get my speed up to 33, then keep enough power so I drop to 27 at the peak. If I'm faster than that, then I need to tap the brakes near the bottom to stay below 34, which tends to confuse the drivers behind me.

On the trip home, the railroad bridge is near the end, so if I hit the lights "right", the SOC may be below 55. If that's the case, I pull into a parking lot a few tenths of a mile before the bridge and wait until it gets back up to 63.

Since this is the SF Bay Area, the year-round temperature is very mild, so that's rarely a problem. One day when it got about 90°, it went out of EV mode, probably because the battery temperature went high. It never freezes during the day, so I just wear a sweater in the car if it's cold outside.

I have one of the gauges in my ScanGauge2 set to "EV Button" so I can make sure I pressed the button, and if you press it within a few seconds of turning the power on, it will beep when you press it.

Edit: I forgot to say, this is a 2004 Prius with a 4kWh Enginer installed in December 2009.

 

That's tough to do in Sunnyvale. I guess you never have to go across Central Expressway. And hopefully you don't have a Caltrain bearing down on you.

Nice work, though.

 

Sounds like you'd benefit from the 52mph EV hack. If you have a scangauge i think you can clear the engine fault code if you pull the fuse for the fuel pump?

 

Speaking of planetary alignment, does the gear box (CVT) still get lubricated even when the ICE is off? And what about the cooling of MG2, is it really independant of whether the ICE is on or off?

If that is not the case, it would be unwise to travel long distance in pure EV and might damage parts of the engine.
Does anyone know?

 

I just thought I'd make an update to this post. Since I installed the enginer kit last night, I've had a chance to test the new 5000W converter. Unfortunately, it looks like long-EV trips are not possible. I did manage to go about 3 miles in EV mode before the the SOC of the hybrid battery became too low. This was mostly on flat ground at around 30 mph. Longer trips may be possible on downhill slopes or other stop-and-go traffic.

 

did your new kit came with BMS? is it the same one shown at green drive expo with USB attached to a readout?

 

Hi David,
I just did better than you I think. Any way the point is that Enginer is not aimed at pure EV. It will get you close and I expect that with some practice you will achieve your goal. However, there are temperature and smog and other issues. Enginer does not change or spoof the Prius programing in any way. Because of this it works best if you try to minimize the ICE but do not try to eliminate ICE use all together.

I got 8.5 miles at 99.9mpg with an average of 24mph. This included warm up. I did a peak of 55mph with the ICE running and 42mph with the ICE not spinning. I started and finished in my garage. I started at 7 bars and ended at 5 bars.

Thanks,
Dan Lander

 

Hi cpro,
No, none of the new kits have the BMS yet. I ran my system with CellLogs and obnoxiously loud alarms. This makes it safe. I would not recommend running any system without some way to know, and shut down, if any cell goes high or low. My alarms give me that capability.

Thanks,
Dan Lander

 

Something that still puzzles me: the Enginer kit is limited to about 14 to 15 Amps because it may throw a trouble code when it exceeds that. But when at high speed I hit the break really hard it may regenerate 120 Amps into the HV battery. Why does that not trip a DTC but the Enginer kit will? Or is it because the Enginer system provides these 'fairly high' currents over a prolonged time?

@Dan: I ordered the new V5 kit and it will arrive near the end of November. Do you think it is wise to use additional Celllogs with this new system anyway? It seems with the LCD of the BMS on the dash you would be able to keep an eye on almost anything.

Floyd

 

Do you really know that as a fact?
Is it there any tech info or sales page that it is prompting the USB interface?
I rather wait over 6 months after all the bugs are worked out of the system from the real release day to the public. Knowing the Enginer trajectory......of guinea pigs purchasers.

 

Hi Floyd,
The Prius is smart. It knows about re-gen and allows it. It does not know about Enginer. The Gen2 Prius only allows a limited amount of added current from a source that it does not know about.

The BMS16D display is not USB. It only uses a USB cable. If you have a USB extension cord with no electronics in it you can extend the cord length. The supplied cord will not reach the driver.

You will not be able to keep an eye on the BMS16D anyway. You can not drive and watch this display all the time. If you drive you will eventually not see an event that you were looking for. The CellLog alarm only works because I made it so loud that you cannot miss it and so obnoxious that you want to turn it off.

No, you do not need CellLogs if you have a BMS16D because the BMS16D automatically turns the system off before damage.

Thanks,
Dan

 

Ev mode is great for driving thru a school zone, but not very realistic for all around driving....if you live in a town that is totally level, with
several school zones and businesses, then you might do well with this system.... For the rest of us, we will have to wait until they develop a
system that can do 40 mph for 10 to 20 miles....

2010 blue metallic.....53.7 mpg

 

Thanks Dan! From what I've seen the new BMS also has a slot for a memory card, do you know anything about that? On the Enginer forum it turns out it stores information in xls format. I have some old SmartMedia cards, don't know if that is the right type.

My kit should arrive within a few weeks. Looking forward to it.