I know that heat can kill the battery. The summers here get really hot. Is there anything I can do to help protect both HV and aux batteries from hot summer weather?
park in the shade, run the a/c full blast when driving, get an obd that alows you to run the cooling fan at top speed, and keep it clean, along with the battery modules
Yes, I've found the best way for me to keep passenger compartment temperatures reasonable was to leave both of my front windows open about 3/4 inch. I installed the dark colored rain guards on my front windows so the window being cracked open isn't obvious. That small amount of 'breathability' resulted in an absolutely amazing difference in temperature. Prior to it, there were days I couldn't stand getting into the car after work. Afterwards, it went from being like an oven to barely different from outside temperatures.
Get your FOB updated to lower all the windows at the same time. It's a handy way to quickly vent heat upon approach when you weren't able to do anything to prevent the interior from getting hot.
I worry about heat, mostly while the car sits in the garage. In summer our garage interior gets really hot. Run a warmed up car in, shut the doors, it's slow death in there. The doors are west facing, really transmit the heat. I've put a thermostatically controlled fan in a north-side window, helps slightly. I've toyed with insulating the big west-side doors, but not sure how to approach it. They're solid wood. Or replace, with insulated core steel, but a big expense. And blow some insulation into the walls and ceiling.
Where I live (Yuma, AZ) it consistently hits 100°F + in the summers while sometimes hitting 115°F + (47-48°C) and even the occasional 120°F. In the car, it will get hotter than those temps if you don't use some sort of shade. Where I work is remote and there is no shade spots. I just crack the windows and use a sun shade. Once I get in the car I blast the AC (obviously since it's hot as hell) and never have had issues with my 2007 Prius or the battery. It has 167K miles on it and runs strong. Battery seems fine and haven't had any issues. I also climb a decent mountain grade in 100°F + temps when I travel between Yuma and San Diego and when I do that, the battery gets drained pretty fast and I do lose quite a bit of power, but I believe that's the battery starting to show its age and needing replacing soon which seems pretty standard around this mileage. Gotta remember that these Priuses are used all over Phoenix and all over Arizona and Toyota has tested these batteries for all sorts of conditions, not just for perfect California weather. Sure, the heat may affect it a bit, but operating it in hot temperatures is not going to do much to it as along as you run the AC full blast and let the cabin cool down. I still manage around 45 MPG on my 36 mile round trip commute going 65 MPH and blasting the AC. What is important in hot weather environments is regularly changing your engine oil, tranny oil, engine filters (hot environments usually means dusty as well) and using high quality fluids.
They make strips of foam core panels that slide into segmented garage door panels. Seems effective, though not perfect. Something like : Cellofoam Garage Door Insulation Kit (8-Pieces)-Garage Door Insulation Kit - 8 pcs - The Home Depot How about a picture of the doors in question? Must be a gen3 thing
Get a Weathertech sun shade there insulated and custom form fitted to the car. Mine is 13 years old and still in good shape. They sell it here in the prius shop. First thing I buy for a new car. That and leather wheelskinz for the steering wheel. Mine is 13 years old too still looks good. The G2 wheel is very harsh on your hands. All that white dust on your dash is skin from your hands from that cheese grater steering wheel. Pull out the fabric package cover in the hatch to cover the hatch area. I cut a piece of foil covered insulation board and put it over the top of the fabric hatch cover so sun cannot hit that back package rack area. Its bungee'ed to that cover. Get the best window tint you can afford. Always park in the shade in a parking lot no matter how far away it is from the store. make sure the battery vent fan is clean. if you have a badly shedding doggie put a piece of ac filter over the backseat fan inlet so it does not suck dog hair into that circuit. That battery fan is always running when the car is in ready just at a low speed so you cant hear it. When you hear it that means the hybrid battery is seriously hot.
Mine is west facing too. I replaced my garage door a few years back Dade County rated and a fully insulated door. Oh boy what a difference! 100% improvement best money spent. It was $1800 installed. Sorry i waited so long. The backside feels cool when the sun is on it. Garage is not hot anymore. I got a new roof with lighter colored shingles too. That really helped. As a temporary mitigation go to Home Depot or Lowes and buy the 8 foot long plastic roll up and down with a string shades and hang it outside the garage door to keep the sun off it it. That works pretty good. They come in different colors. The 8 foot long is $29.99 here. Anything to keep the sun off that door. It will greatly help.
Other than cleaning the battery fan, there's really no maintenance on the HV battery (aftermarket grid charging excepted) so the above good advice only pertains to the rest of the vehicle. I'd suspect that regular exercise of the HV battery for long periods (with cooled interior air) such as: makes for long life in very hot weather. Except for 2009 owners, other older gen 2 owner in AZ and other hot locations still running on the original battery has been doing more right than wrong in terms of care/use. IOW, keep doing what you're doing! IMO.
