Too hot to grid charge or bad bat?

[thedhgroup]

Originally Posted by Eli

Oh wow.. Yeah, 700mA is a lot. I have no experience with that. I just hope you didn't cook your pack.

700mA would be a good bulk charge, but I don't think you want to be topping your pack off at 700mA???

That's why everyone has 350mA chargers.. It's safe to give topped off cells 350mA while the others catch up. I don't know about 700mA.....

Also, I open both doors and the hatch to increase air flow when grid charging no matter what the temperature.

Yeah, doors and hatch are open as well as the storage pouch was out. I have the charger set to 169 and at 168 it was pulling about 200ma so I would think it would not be generating a ton of heat but at that voltage almost all the current would probably turn into heat. I have not charged at all today since the outside air temp is still over 90 degrees at 9pm! Just for kicks I put a 8 inch squirrel cage fan blowing into the battery cooling inlet and went back to the hatch. Holy buckets the amount of heat still in the batteries was unreal! I hope to heck I did not fry them last night.

I'm also thinking that I would like to make some modification to where the hot air goes after it leaves the factory fan that sucks the air across the bats. It seems like the heat kinda gets trapped in there and then ends up heating the outside of the battery pack. The holes in the compartment are on the bottom and the last time I checked, heat goes up. Maybe just another fan to suck the heat out of that compartment? What have others done? Maybe time to search the forum.

[Eli]

Ahh. Yeah, being conservative on the voltage of the charger would be a good way to mitigate things. I have my 350mA charger set to 176V after the diode drop.

Regarding the cooling of the battery... yes, I think the whole setup just sucks. I recently ordered a Honda Civic Hybrid battery blower. I'm going to attempt to re-work the entire battery cooling system on the Insight. Both to increase air flow and to change the air source. In my experience it is always hotter in the cabin than outside(I never use A/C). I want to be able to draw air from either the outside or the inside, my choice, depending on the temperature of everything; outside temp, inside temp, battery temp, etc.

I plan to reverse the flow of air and have it pull cool air from outside through the pack and exhaust it next to the passenger seat for the summer months, and having it closer to stock for the winter months, with the option of bringing frigid winter air through the pack if it begins to heat up.

[thedhgroup]

Well, it is heating up in the Midwest again. I decided that I'm going to try to get some of the hot air out of the hybrid battery area. Couple years ago I snarfed a small squirrel cage fan from the city dump. I figured it would be useful some day. So I'm putting it to good use. It is a 110 volt ac motor so I'm only going to use it when grid charging for now.



I just about had the pack topped off since it was throwing some heat. It is crazy how much heat comes out of the little blower. It is mounted just to the right of the storage area. I may duct it to the air vent thingee on the right rear. I think that is where the hot air is supposed to come out anyway.

I think the next time I have the back open I'm going to mount a thermostat sensor in the pack that will turn off the charger if too hot. I'll go back to the city dump and get a sensor and switch from a discarded window air conditioner. For now I just use a timer to tame things down a little.