[azKiaUser]

So I wanted to know what the max temperature in the frunk could be (during the current heatwave). Obviously this would be dependent on the ambient temperature.

I wanted to keep/store a 12V battery booster--just because...Or maybe a laptop for a day or so.

Lithium batteries don't like high heat and an interior could hit 80C. Most battery boosters have a max storage temp of 60C (I think one was 70C...but can't find it now).

I couldn't find this info anywhere so I decided to test it out for myself. Non-scientific of course

I purchased a Elitech RC-51 Digital Temperature Data Logger and taped it inside my frunk.

I recorded all the temps encountered for a couple days; in my garage as well as a few hours out in the sun.

My MAX temperature in the sun was 46C with an ambient temp of 36C.

This was consistent for a couple days. It appears as though the frunk temp is approx "ambient + 10C".

I found frunk information for a Tesla and it was significantly higher in the frunk (non-scientific...non official specs). I think the EV6 does a better job with insulating the frunk. If you see the pics below it looks like the hood has some type of thermal barrier as well as the (little) frunk enclosure.

Anyway, thought it was interesting...I'll continue logging a few more days and maybe see what the interior temp gets to (my tint is a few weeks away...)

 

[windracer]

We still haven't figured out what to store in the frunk ... maybe a flashlight? Most of that kind of stuff (charging cable, etc.) we keep under the cargo deck.

 

[Ian Mac]

So I wanted to know what the max temperature in the frunk could be (during the current heatwave). Obviously this would be dependent on the ambient temperature.

I wanted to keep/store a 12V battery booster--just because...Or maybe a laptop for a day or so.

Lithium batteries don't like high heat and an interior could hit 80C. Most battery boosters have a max storage temp of 60C (I think one was 70C...but can't find it now).

I couldn't find this info anywhere so I decided to test it out for myself. Non-scientific of course

I purchased a Elitech RC-51 Digital Temperature Data Logger and taped it inside my frunk.

I recorded all the temps encountered for a couple days; in my garage as well as a few hours out in the sun.

My MAX temperature in the sun was 46C with an ambient temp of 36C.

This was consistent for a couple days. It appears as though the frunk temp is approx "ambient + 10C".

I found frunk information for a Tesla and it was significantly higher in the frunk (non-scientific...non official specs). I think the EV6 does a better job with insulating the frunk. If you see the pics below it looks like the hood has some type of thermal barrier as well as the (little) frunk enclosure.

Anyway, thought it was interesting...I'll continue logging a few more days and maybe see what the interior temp gets to (my tint is a few weeks away...)

View attachment 6659
View attachment 6660

That's not bad. I bet the RWD models will be quite a bit higher as they don't have the bonnet (hood) insulation installed.

 

[azKiaUser]

We still haven't figured out what to store in the frunk ... maybe a flashlight? Most of that kind of stuff (charging cable, etc.) we keep under the cargo deck.

Yeah...I was thinking kids laptop/phones, etc. If you go hiking for the day and leave your car out in the sun the interior temp gets really high.

 

[MikeV]

Tested the temps in my frunk (EV6 AWD) in the direct Tennessee summer sun yesterday. The front of the car was placed facing west towards the sun for 1.5 hours from 4-5:30pm. A electric thermometer with an internal sensor and external wired remote sensor was used. The probe was placed in the frunk and the front hood was closed. The reported outdoor temp was 95F, the temp in the shade at ground level 106.7F (internal sensor) and the frunk temp was 120.5F (wired sensor). So it looks like the frunk is about 14F warmer than the outdoor temp. Needless to say I will not be leaving my Li 12v battery jumper in the frunk during the summer. You should probably not leave temperature sensitive items, especially batteries, in the frunk.

 

[Ucinn]

Tested the temps in my frunk in the direct Tennessee summer sun yesterday. The front of the car was placed facing west towards the sun for 1.5 hours from 4-5:30pm. A electric thermometer with an internal sensor and external wired remote sensor was used. The probe was placed in the frunk and the front hood was closed. The reported outdoor temp was 95F, the temp in the shade at ground level 106.7F (internal sensor) and the frunk temp was 120.5F (wired sensor). So it looks like the frunk is about 14F warmer than the outdoor temp. Needless to say I will not be leaving my Li 12v battery jumper in the frunk during the summer. You should probably not leave temperature sensitive items, especially batteries, in the frunk.

It will still probably be cooler than the trunk don't you think?.. also, was this tested on the AWD or RWD version. My understanding is the AWD has extra insulation in the frunk area.

 

[azKiaUser]

Tested the temps in my frunk in the direct Tennessee summer sun yesterday. The front of the car was placed facing west towards the sun for 1.5 hours from 4-5:30pm. A electric thermometer with an internal sensor and external wired remote sensor was used. The probe was placed in the frunk and the front hood was closed. The reported outdoor temp was 95F, the temp in the shade at ground level 106.7F (internal sensor) and the frunk temp was 120.5F (wired sensor). So it looks like the frunk is about 14F warmer than the outdoor temp. Needless to say I will not be leaving my Li 12v battery jumper in the frunk during the summer. You should probably not leave temperature sensitive items, especially batteries, in the frunk.

I think our readings are similar. I went from 97F to 115F (36C to 46C)

I see jumpers listing max storage temps at 140F. Operational is lower.

I basically was trying to figure out if you wanted to, or had to, store a Li battery would it be better in the frunk or interior. Neither is ideal.

Not just for long term storage like a jumper, but if you have your laptop after work and go to an event should you leave in your car interior or put in frunk...assuming it fits

 

[MikeV]

It will still probably be cooler than the trunk don't you think?.. also, was this tested on the AWD or RWD version. My understanding is the AWD has extra insulation in the frunk area.

I tested the temps in an AWD EV6.

 

[RSinAZ]

Nice work AZKiaUser and MikeV. Thanks.
I'm in Tucson and hadn't thought about this as I'm retired, so the car mostly spends it's time in an insulated garage that maxes at 95F even at 110F outside.
I keep a jump starter in the frunk. However, next year it'll be in a Phoenix hotel parking lot for 2+ weeks while I'm in Europe. The car is Interstellar Gray, RWD (did I mention I was retired?). So the dark hood over the frunk seems the worst of a set of poor choices. The car will be charged around 80% when I park it and the 12V top-off seems to be working, so the jump starter was Plan B. I'll stick it under the passenger seat now. It'll help a wee bit. And for Plan C, there's always AAA.

 

[MikeV]

Nice work AZKiaUser and MikeV. Thanks.
I'm in Tucson and hadn't thought about this as I'm retired, so the car mostly spends it's time in an insulated garage that maxes at 95F even at 110F outside.
I keep a jump starter in the frunk. However, next year it'll be in a Phoenix hotel parking lot for 2+ weeks while I'm in Europe. The car is Interstellar Gray, RWD (did I mention I was retired?). So the dark hood over the frunk seems the worst of a set of poor choices. The car will be charged around 80% when I park it and the 12V top-off seems to be working, so the jump starter was Plan B. I'll stick it under the passenger seat now. It'll help a wee bit. And for Plan C, there's always AAA.

You could also keep it in the glove box but in the cabin may be even better.

 

[avh]

Can you park in a ramp or under a tree in the shade while you are traveling?

 

[RSinAZ]

Won't know till I get there. That would be nice if I can.
Forgot to credit you in the original post. Sorry. Belated thanks for your insight.

 

[azKiaUser]

You could also keep it in the glove box but in the cabin may be even better.

Why would the glove box or cabin be better?

Hot Car Calculator | Time to Heatstroke (omnicalculator.com)

Sitting in the sun...the interior gets hotter than any other part of the vehicle (such as the frunk...or so is my proposed theory).

 

[MikeV]

Why would the glove box or cabin be better?

Hot Car Calculator | Time to Heatstroke (omnicalculator.com)

Sitting in the sun...the interior gets hotter than any other part of the vehicle (such as the frunk...or so is my proposed theory).

My guess is the interior and frunk wind up the same temp but the heat coming off the inverter and front motor should initially raise the temp in the frunk and there is no HVAC cooling it. However when the car is off, the temps will over time be equal. I can test it to see.

 

[azKiaUser]

My guess is the interior and frunk wind up the same temp but the heat coming off the inverter and front motor should initially raise the temp in the frunk and there is no HVAC cooling it. However when the car is off, the temps will over time be equal. I can test it to see.

yeah I've been running tests this week since we've been over 100F...forever.

So far it seems about ambient +10C but the longest I've been out in the direct sun was for approx 4 hours (I'm sensitive about my new car and don't want to abuse...)

I was guessing that the interior would always be much higher (during the day) due to the greenhouse effect.

But you may be right about the inverter motor temps coming into the equation. After getting home, and into a garage, I noticed the elevated temperature of the frunk (the ambient +10C) didn't start to dissipate for a couple hours (it didn't go up tho)

 

[azKiaUser]

I pulled my frunk logging for the last few days.

Pretty much similar. Typically, ambient plus 15F or so.

Interesting thing. My highest recorded frunk temp of 117F (with 98F ambient) occurred half an hour after I got home and parked in my garage. It took another 2.5 hours to return to the temp before entering the garage.

I'm guessing the stagnant air in the garage isn't dissipating the heat as effectively as the air flowing over/through the frunk.

Still...I think the frunk is a better long term storage location than the interior; but not ideal. The frunk temperature seems 'a bit higher' than ambient temperature.