Passive cooling ?

[Malm]

I captured, in video, the moment that AC turns on in a quick charge. See the light turning on. It turns on when a sensor reach 31º C.
https://www.youtube.com/watch?v=r3GePlW1P4E

 

[Aerowhatt]

I captured, in video, the moment that AC turns on in a quick charge. See the light turning on. It turns on when a sensor reach 31º C.

Wow great information to have. I've been hoping someone would be curious enough to catch the temperature that the AC comes on during DCQC. Here is to curiosity!

It's an important number for many reasons. Basically says to me that Mitsu would prefer the cells stay below 33 C. Of course range concerns and charge time concerns outweigh temperature while driving so no such activation there or on L2 either, not around that temp range anyway.

Do you remember what the warmest sensors read after the DCQC was complete? In other words how successful is the cooling at keeping the temps down at 2C charge rates?

Thank you for your diligence,

Aerowhatt

 

[Malm]

The rate of charging will be slower and slower. As you see in the video, the rate of charging is already going down and so, the rate of heating too. I don't remember exactly what were the numbers, but for my experience in cooling the cells, I feel that the system is effective.

 

[pbui19]

thanks for the info about the 30-31C threshold.

Is there a cabin air filter ? I am a little concern about dust/dirt collecting over time with the air flow through the battery pack ? a quick scan through the manual didn't show it

Thanks

 

[PV1]

The cabin air filter is located behind the glove compartment. Squeeze the top sides of the box when it's open and it'll release. Drop it down a bit and it should lift or of the hinge.

 

[Malm]

thanks for the info about the 30-31C threshold.

Is there a cabin air filter ? I am a little concern about dust/dirt collecting over time with the air flow through the battery pack ? a quick scan through the manual didn't show it

Thanks

I think air is always flowing in the pack. One of the vents will always work, from time to time.

Yes, there is a cabin air filter. I check it with some regularity, because I was a little concerned with my behavior of systematically try to cool the pack. I am amazed because it looks to me always very clean. I think the air that goes to pack is very safe (clean, cold and dry). Maybe the benefits for the pack are more then being cooler.

I think the worst enemy of the pack will be the corrosion that happens in time specially with humidity. I have some information that Mitsubishi is concerned with that, in the older packs.

 

[PV1]

I think the worst enemy of the pack will be the corrosion that happens in time specially with humidity. I have some information that Mitsubishi is concerned with that, in the older packs.

I remember hearing reports a while back that corporate was randomly checking cars for this. I'd like to know how they did if they don't allow the dealers to open the battery packs...maybe they sent a specialist?

 

[Malm]

I think the worst enemy of the pack will be the corrosion that happens in time specially with humidity. I have some information that Mitsubishi is concerned with that, in the older packs.

I remember hearing reports a while back that corporate was randomly checking cars for this. I'd like to know how they did if they don't allow the dealers to open the battery packs...maybe they sent a specialist?

I asked myself exactly the same question. How can they do that, without opening the pack. But they are doing it,and I suspect they are doing it in my I-MiEV, because in the last annual check they had the car for three days (in the other three times they had the car for only two days), and they said that they wanted to see my car in the next months again.

 

[pbui19]

Now that it's getting warm, I am starting to monitor the pack temperature again. I was a little concerned yesterday after DCQC and saw quite a few high T at 35C (95F). I was also surprised that the iMiev system didn't have the AC on. It did come on when DCQC was initiated.

Other than the normally high #64 T reading, I am curious to learn what are the highest T every one has been seeing ? at what T is it recommended to force AC cooling ?

Thanks

 

[PV1]

95 F is right about where I kick the AC on for the pack. 85-94 F is where I am at least blowing ambient air in as long as ambient is below 80 F. For my normal everyday driving with just me in the car, I don't usually get the pack that hot and use timed level 2 charging to maximize night time cooling.

 

[rnlcarlov]

The highest I've ever seen was 42ºC on a couple of cells after a quick charge. And this happened since my AC broke down when I was 200km away from home. Apparently the Cooling Fan Motor went kaput. So while AC worked during cruising (since the wind was enough to cool the condenser) when it came to Quick Charging it was a no go. It stopped working halfway through my first QC and didn't work at all on my second QC.

This was quite recent and my AC still isn't fixed. The repair price was a bit too high for my liking, so I'm ordering the part by myself and I'll take it to a car A/C specialist to get it changed.

 

[Lic]

The remote Cool option doesn't blow air to the floor.

I added 2 resistors to simulate that air dumper in "all to face" position and now remote Cool option blow air to floor too, so it will cool battery when car plugged to AC.

 

[Phximiev]

The remote Cool option doesn't blow air to the floor.

I added 2 resistors to simulate that air dumper in "all to face" position and now remote Cool option blow air to floor too, so it will cool battery when car plugged to AC.

Do you have a pic?

 

[Aerowhatt]

The remote Cool option doesn't blow air to the floor.

I added 2 resistors to simulate that air dumper in "all to face" position and now remote Cool option blow air to floor too, so it will cool battery when car plugged to AC.

Do you have a pic?

Yes some details please . . . that is a great idea!

Aerowhatt

 

[Lic]

I measured resistance in different position of air dumper. If you look scheme (http://mmc-manuals.ru/manuals/i-miev/online/Service_Manual_2011_2012/img/90/HCT12E00EC00ENG.pdf) air dumper has motor and resistor which tells to AC controller in which position air dumper right now. My idea was to install air dumper to position - blow to face and floor, but modified resistance like in all to face position. Resistance between 33 (control wire) and 38 should be 680 Ohm and between 33 and 34 should be 2.9KOhm - all to face position. Resictance in blow to face and to floor position are 1.67KOhm and 2.6KOhm . I disconnected control wire (contact 33) from AC controller (under AC knobs) and put 300 ohm resistor between AC controller and control wire and I put 1KOhm resistor between contacts 33 and 38.

 

[Aerowhatt]

I measured resistance in different position of air dumper. If you look scheme (http://mmc-manuals.ru/manuals/i-miev/online/Service_Manual_2011_2012/img/90/HCT12E00EC00ENG.pdf) air dumper has motor and resistor which tells to AC controller in which position air dumper right now. My idea was to install air dumper to position - blow to face and floor, but modified resistance like in all to face position. Resistance between 33 (control wire) and 38 should be 680 Ohm and between 33 and 34 should be 2.9KOhm - all to face position. Resictance in blow to face and to floor position are 1.67KOhm and 2.6KOhm . I disconnected control wire (contact 33) from AC controller (under AC knobs) and put 300 ohm resistor between AC controller and control wire and I put 1KOhm resistor between contacts 33 and 38.

Very interesting idea! Thanks for sharing the details, something I will be looking into when time permits

Aerowhatt

 

[nhhecker]

I didn't like the idea of removing parts. I loose things when put away in a "safe" place. So I did some research on the actuator. Turns out it is not smart at all. I unplugged it and used a 9 volt smoke detector battery to trick it into moving to the full air to the battery duct position.

I've been using an alternate method to trick the actuator, which I'm sure has been done already, but I didn't see it documented in this thread.
1. Initiate CHAdeMO charging session and allow car to use AC to cool the battery.
2. Unplug actuator connector.
3. End CHAdeMO session and drive away. If you want to return things to normal (in the event of Mitsubishi service or cold feet), just re-attach the connector and turn on the car.

I've since used DCQC a handful of times with the actuator unplugged like this, and haven't had any issues, lights, or errors. Caveats are that you can't direct air to your feet anymore until you plug it back in, and that you must find a CHAdeMO station to get it in the 'battery-only' orientation. (Or you could use a 9v as Aerowhatt suggests.)

I live in Atlanta, GA so the winters are pretty mild and I haven't had cold enough feet to warrant reverting this back. (Although I did have a PM service today, so I plugged it back in this morning!) I thought batteries liked being cold-ish, anyway? It's not usually below 0C here.


Nick

 

[nhhecker]

Oh, and a question for anyone who's been using any of the methods mentioned in this thread in order to manage their battery pack's temperature:

Has anyone else noticed an acrid smell in the car after charging, or sometimes after rapid acceleration while under way? I don't know how to describe the smell other than it being acrid / acidic / strong / maybe sort of with a cooling sensation, like when you smell menthol or acetone or similar, if that make sense.

I imagine that the source of the odor is gas given off by the battery pack while charging / discharging, but I haven't tried to really locate the smell, and it usually dissipates if I blow in fresh air or leave the windows down for the first few minutes of driving. Just me? I'll probably leave the actuator in stock configuration for a while and see if the odor goes away.


Nick

 

[PV1]

I get a weird smell if I accidentally leave the airflow to the battery (floor).

That method definitely would work, but I went one step further and simply unplugged and removed the actuator. The benefit is that I can reach down and flip the damper on the fly.

 

[kiev]

That sounds like the smell of the Lithium electrolyte from when a cell is venting, but there shouldn't be a return path for the battery cooling air back into the cabin.

Do you have CanIon and the obdii dongle--maybe a weak cell would show up on CanIon, or good time to monitor cell temperature during chademo charging.