Enginer PHEV DC/DC Overheating issues

I have the 4kw system but was shorted the jumper wires to connect all batteries together (my case is full). So technically, I have the 4kw set up, but I am only using 2kw for now. As soon as my other batteries are hooked up, I will monitor the temp of my converter very closely.

JOANNA

 

Thanks Joanna, it's good to know that this issue is not affecting all systems in the 4KW configuration. Hopefully it will be limited to the few that have been reported.

 

We have been working with the customers on the overheat issues. The two overheat issues are caused by improper settings in the converters.

However, our supplier is serious about any potential defects and re-designed the enclosure for better ventilation (added 4 inches fan on the left, moved the charger to the right and added a few air intake holes). The test indicates one hour continuous full load without interruption.

There will be some delay for the 4KWH system delivery as the result of the changes. 2KWH system is fine as the way it is and can be shipped immediately.

 

Thanks Jack, Please make sure I get one of those rejiggered converters. A delay is fine with me.

Rob, Victoria CAN - paid you today.

 

Thanks for the update Jack. That sounds good... except for the delay...

 

OK, this is about overheating (or very hot anyway), but not about the DC/DC converter.

With Jack's help, my unit finally started running yesterday. I got home and plugged it in to recharge, then left it for a half hour or so.

When I looked in on it again I found the steel case was VERY warm to the touch, esp. in the lower right where the charger is. Understandable since you expect it to get warm during recharging.

Well, with the cover closed and the trunk floor mat over the top of everything it was starting to get like an oven in there. I pulled back the floor mat and opened up the cargo cover to let some air in there. I checked back again in another half hour and it was still hotter than I liked, so I got a couple of blocks of wood and propped the lid open an inch or so and that seemed to help.

Need to find some way to improve the ventilation to the box.

 

Same issue here, even with the replacement DC/DC converter that is definitely running cooler the box is still too hot to keep confined and packaged up when it's running. I've had to keep the side compartment, to the left of the box out and left the trunk cover folded half way open to allow heat to escape and even then it's quite hot to the touch after some drive time.

I ordered 2 higher CFM fans and when they show up I'll be using one for direct venting (again) out of the box and through the side panel and the other for drawing air from the cabin into the box. Venting isn't a problem (my last rev was a less powerful fan and some duct work) and will be nice because when this thing is running uncovered I notice the hot air in the cabin competing with the air conditioning. I'm not sure how/where I'm going to draw in air from the cabin though. I'd really like it to look as stock as possible when you look in the trunk, all closed up you know?

Did you move the charger out of the box? That was a suggestion from Jack early on to me anyways and it did work pretty well at both adding air flow to the batteries as well as keeping the box cooler during charging. I've got mine mounted in the spare tire area so after charging anyways my box no longer is hot to the touch.

 

Just wondering, but how hot is too hot? Are you still experiencing overheating problems with the replacement converter or are you just concerned that the box is hot to the touch?

 

Sadly yes, I have still experienced the overheating problem but it is a lot more manageable. If it's already pretty hot in the car from it sitting during the day and I start out I can only run for about 20-25 minutes maximum before it fails due to overheating. This seems independant of windows open or closed or AC level. I haven't measured the temperature it's reaching (yet, I've been pretty frustrated lately by some of these setbacks but I'm resuming logging data including temperature at the end of this week) but I know the case is too hot to touch. If it's cooler or first thing in the morning when the car hasn't been heating up all day it seems fine. I've driven with it running for about 45 minutes wihtout issue under those circumstances.

I do already have tinted windows and a windshield sunshade. I also ordered those window vent things so I can keep the windows cracked open when it's sitting all day without worrying about rain getting in. All to keep the inside temperature as low as I can during the day.

That said, the converter is still prone to overheating the way it is. I'm planning on adding a second one in parallel (like you had mentioned in a different post) once I get the venting/cooling issues worked out so I can get more current into the car for better EV use but I am real concerned about ventilation issues since obvoiusly 2 is going to make the issue that I'm having with one much worse

 

Hey Jack,

Is the metal case getting too hot during charging an issue you're working on? If so, what's the possible solution? I'd like it applied to my kit.

 

You guys might want to check this out:

PriusPlus-Instructions - EAA-PHEV

This is an electrical mod that allows manual override of the OEM battery fan which draws air in from the cabin while still letting the Prius turn it on when it wants to. I believe you would override and turn the fan on by grounding the black wire (pin 5). The diodes prevent your override signal from damaging the upstream controller, but still gives the controller a path to be able to turn on the fan itself.

Not sure it would be helpful in this case, as its pulling air in through the battery case into the plenum and out the outlet, but thought I'd get the info out there in case someone can make use of it.

Rob

 

Pictures?

 

The new 4KWH system has ventilation fan built-in the box. It turns on when the temperature in the box exceed 120F (50C) during charging and discharging.

 

I think that the threshold point of 120F is to high for an enclosed carrier of this type, probably 100F would be more adecuated.
Also, is it there an inflow ventilation openings in the case?

 

I think a slightly lower threshold would be better too. But we might have to see.

 

I believe there are holes in the bottom of the new case. At least it appears that way in the picture. I'm sure Jack will confirm.

 

I always thought the "weak link" was the balancers specked at 115F (may even be lower, can't find the info).

11011011

 

mottcell battery's?
so no longer the yellow thunderskys?