Are batteries lasting longer when they're located outside the engine bay away from the heat?

Well, I am going to say, NO! When they're in the engine compartment, they are right in the way of cooling air coming into the engine bay. As were the batteries that are located in the trunk or backseat area, or even the wheel well of the car(Chrysler), don't seem to show any benefits for longevity. I think the battery placement is for weight balance.

Batteries that are in vehicles living in the HEAT BELT suffer from more earlier failures regardless of their location in the vehicle. Batteries not maintained also fail early regardless of the location in the vehicle.

This is just my opinion.

CB

I'm gonna go with "yes".
As the temps are more stable and generally cooler when away from the heat of the engine bay.

I’d say the battery being out of the engine bay would be better for it, but I’m sure the engineers don’t care about the longevity of your battery. They are probably doing it because of less room under the hood.

I thought batteries in today's cars were maintenance free? If not, I better start doing some maintaining, after I figure out what needs to be done.

I agree with Ryan, heat is not the primary reason the battery is moved from the engine bay. Wherever the battery sits, corrosive vapors is a concern. Plus, the longer cables will reduce the power available for starting, unless the cables are thicker.

I have owned cars with batteries in all locations. Cooler is better.

Can definitely help. Its somewhat known that batteries in the 2014+ cherokee live short lives.. due to excessive heat.
Many going before the 3 year mark... even in the years previous to having auto start/stop.

Depends on the location. In Canada it might help stabilize the temp for cold starts if the battery is located inside, and less exposure of connections to a corrosive atmosphere. The resistance from the wiring might negate these advantages.

Have you ever seen industrial vehicles where the battery is just hanging off the side of the frame? I do not think it matters one way or the other.

A battery mat to absorb shock, keeping the case clean, the water level proper if it has caps, and of course the terminals clean and corrosion free (and a light film of oil or grease if that's your thing) is all I think is needed in a regular car. Of course regular charging if it is rarely driven or a detached negative cable are good.


A Cobalt I had placed the battery in the spare tire tub/well low in the trunk. It has a vent hose for (hydrogen?) fumes- but dont AGMs solve that issue? I think that is a perfect location for a sporty car for the weight issues. Also, the battery is out of the way for more room in the engine bay and also, smokers and those careless can be safer not having it under the hood when doing work to the car.


As for do they last longer....I would guess they would with all things being equal. But if you treat your underhood battery like royalty then they would probably last equal in time. Its just with the battery inside it probably require alot less attention and that is good for the masses......like sealed non-greasable steering and suspension components.

YES they are.
Chevy cobalts can easily go 8 years or more on a battery because it is mounted in the trunk out of the temp extremes, vibration, and eposure to liquids dirt, and corrosives.

MIL's lesabre got 12+ years from the stock battery under the rear seat and wife's HHR was sold at year 10 (11?) with its OE trunk battery.

If having 3 batteries (includes the original) in 18 years for my 2000 E320 Mercedes is any indication...the answer is yes...having a battery away from outside elements helps longevity.