Will it damage the hybrid battery if I blow water mist into the ventilation duct?

If you were to clean the corrosion off once a year and replaced the voltage sensors wires regularly maybe you could get away with it? I think the real concern is if your water system fails or you miscalculate and too much water gets inside there. Could create big problems. As long as you're using your air conditioner when you drive in hot weather and you got a vent sending cold air towards the intake there's no need for evaporative cooling.

 

sounds like a bad idea, why not just turn the fan on full speed?

 

Do not ! If you want to cool it like you do your liquid cooled PC you need to look into that you'd have to make up some kind of a jacket to go around the modules so on and so forth it could be really involved that's why Toyota went with nickel metal . If you're going to do all that just re-engineer a modern $211 v base battery with however many AH you can stuff back there probably not really worth your time but by all means have at it I wouldn't just be blowing water through my case even a very fine injected mist would seem to be not a good idea.

 

Water mist into a high voltage area is a very bad idea. Do NOT do it!

 

What led you to this plan? Toyota has thermosensors on the battery, and a multi speed fan to cool it, and programming to run the fan as needed to avoid damaging the battery. Why second guess them?

That aside, introducing water droplet may cause corrosion. Or electrical short circuits.

 

It would create a high voltage leak and cause massive issues.

 

you can search around. pretty sure there are a few threads on customizing ductwork and fans.
do you keep the cooling fan clean and intake grille open?
you can monitor battery temp with an obd.
it might be worth opening and cleaning inside the battery case. the inner modules get the hottest and fail quickest. someone rearranged things to alleviate that problem.

 

What is ideal temperature for a battery? Or this type of setup what are we looking for You guys always talking to around 110° hell that's only a few degrees hotter than my body generally sits at rest we're at 97° almost 100 and you're talking 14 more degrees and everybody's panicking and getting worried seriously is 110° too hot for a nickel metal hydride battery assembly I'm just trying to understand what we got going on here I mean when I reach under my battery after a hard run or running around for a couple hours and all of this and that when I had the battery open and access in the back I could reach under my battery a little bit and feel the bottom plate and it would be about for a little warmer than I am say 110° maybe 112 I thought this was perfectly reasonable would I really want to have ice cold air blowing refrigeration freezing air on this band is my end game to keep the battery 65°? Is that what we're looking for nice and cool like air conditioning so I want electric motors and batteries and all that kind of stuff to never get warm We want to keep them like 72° ideally would be perfect forever seriously is that correct I'm just trying to understand what we're looking for I realize in Tesla's and all they're using water cooling whatever the methodology is like a radiator for the batteries but then again look at the size of those batteries the voltage they're running 600 whatever it is that might require quite a bit of cooling again one would think to be maintaining probably close to 100°. I mean like you don't want your engine coolant to always be 73°, it needs to get up to operating temperature so that other systems can function properly Not saying electricity is the same way but at some point I mean we wouldn't want to have our batteries and Antarctica that cold because then performance goes down so there must be a happy medium here?

 

If you are serious, you can take some duct and run if from the right outer
a/c vent and either up or down to the fan intake. Then you have much colder
air going right into the battery.
If you feel the battery is still overheating, you chould open everything up and clean
any dirt or fur or whatever is stopping the air flow. Because that is likely why it's running
hot, if you run with the a/c on. And/or you have bad modules that are overheating because
they're sucking up so much juice they are over heating...

 

Darker tint & turn up the AC another notch.

 

What are optimum temperatures for what we're dealing with here? I mean in everyday run of the mill situations with a battery this size so on and so forth what kind of temp should we be looking for can't be the lower the better because once you get down into the close to freezing range that's when battery start to have problems right so there must be a sweet spot 40° to 68° or something like that does anybody really know just seems to me like a hundred degrees or 105 or 10 I wouldn't think would be it of course I can be wrong I would just like to know how wrong I am I know my 12 volt just sitting in the trunk anytime in the summer is going to be sitting right close to 100° the interior of the car will get to 130 or 40 easily in the sunshine The dashboard top almost egg frying if you park like most people I see parking not me personally but other folks my car is always in the shade almost everywhere I go I will walk an extra 500 ft to put my car in the shade without question maybe that's why they're not falling apart so fast at least exterior and interior and trim which is what I care more about than the car running I hate it when all the plastic is turning white and stuff is just falling off of things because it's turning to dust.

 

toyota has printed temperature parameters

 

I would not worry about it unless you get a battery temp code. The only real “mitigation” some have done is to set a higher fan speed with an app like Dr Prius even though Toyota does this automatically based on current battery temps. The downside of app control is the app has to be up constantly to overwrite Toyota’s control. In the end it’s a waste of time.

There have been tests in the past where 105f ambient produced 125f hv battery temps.

One member reported 150f battery temps without coding any of the three battery temp sensors. Another reported a code at 138f when the battery fan failed. So it is likely 125f is fine and 150f still acceptable if the fan is running.

Obviously if it is 75f up north the battery will run a few degrees cooler than 105f ambient in Texas.

Keeping the heat out of the cabin is the best solution since the battery fan is pulling air from the cabin, routing it over the hv battery and then dumps heated air outside. Having the AC functional allows 75f in the cabin with 110f ambient. 99% uv rejection window film helps as well (which can be clear on the inside of the windshield).

Finally cool air won’t revive a weak battery. A new oem pack solves that problem plus you get better acceleration and mpg as a bonus.

 

Shocked that no one said that after many posts.

 

Yep. The battery pack dropped 20F in 30 mins during 100F summer temps after 8 hours parked in direct sunlight.

 

The definition of overheating is the issue. It is not overheating at 110f and is in fact cooler than some hybrid batteries. Sometimes we think batteries and mechanical devices are like humans.

The inverter cooling system is something with a low trip point of 149f. That can be reached on a 105f day while sitting in a significant traffic jam with the AC on high.