air filter or maintenance for battery pack cooling?

[Red]

was thinking on the drive home about how you have to change the engine and cabin air filters on a maintenance schedule, and wondering what prevents the HV battery cooling running in tip top shape.  I have not seen or read anything about an air filter for the battery pack, so am I correct in assuming there isn't a dedicated filter for it?

 

beyond that, has anyone torn down a higher mileage battery pack and observed significant dust bunnies in the pack?

 

it occurred to me that in the heat of last summer, I may have frequently pushed the battery pack hard, which also leaves me wondering if there is a way (through Forscan or some other tool) to increase the fan speed/curve to increase cooling on those 100 degree summer days.  thoughts?

[jsamp]

Since the air intake for the battery is from the rear deck inside the car, they may be assuming the cabin filter has already filtered the air.  That assumes you don't roll down the windows when driving though, so a weak assumption at best.  I have not heard of a replaceable filter for the battery or charging unit.

 

I don't know much about Forscan or other scanner tools, but I doubt you could make any changes to the fan curves.  It sure would be nice though.

[cr08]

As noted, there's no filter on the HVB. ForScan does essentially have a 'test mode' option to manually take control of certain actuators in the car and one is the HVB fan. But there's no way to adjust it's own operating conditions/temp curve outside of that. I know one distant 'pie in the sky' idea I had wanted to try with my own vehicle at some point is build a microcontroller that I can leave installed in the vehicle and have it force the fan to run under conditions I desire. But that'll require some reverse engineering of the CAN bus data which is my biggest roadblock.

 

In the C-Max community, there has been one member who has figured out some details on the cooling operation of these batteries. Given the similar powertrain to the Fusion Hybrid/Energi I imagine the operation is not any different but don't quote me 100% on that. But one key point is that the cooling fan will only come on once the interior cabin temp is at least 20 degrees F below the battery temp. If it's within that window, even if the battery is near overheating, it doesn't do anything. Even then the cooling system is pretty inadequate and even with Max AC and the cabin being an icebox, the battery doesn't cool down fast enough during normal, full EV operation. And I imagine for the Fusion being largely buried inside the trunk (The battery in the C-Max is entirely inside the conditioned cabin space) it just makes it worse. Monitoring the battery temp and keeping it in check is absolutely essential if you worry about longevity and maintaining capacity.

 

Also a semi-unrelated note, but worth mentioning: When plugging in to charge, you may hear a cooling fan running from outside the car. This is just for the onboard charging module. Under normal 'key off, get out, plug in' operation, the battery cooling fan will never come on. Some have tricked it by plugging in while the car is still running and then shut it off. In very hot conditions, avoiding charging or at least limiting to L1 is preferable.

[jsamp]

On 3/6/2024 at 7:11 AM, cr08 said:

Also a semi-unrelated note, but worth mentioning: When plugging in to charge, you may hear a cooling fan running from outside the car. This is just for the onboard charging module. Under normal 'key off, get out, plug in' operation, the battery cooling fan will never come on. Some have tricked it by plugging in while the car is still running and then shut it off. In very hot conditions, avoiding charging or at least limiting to L1 is preferable.

 

I've had that fan come on sometimes and others not when plugging in.  I've even had it come on when I plug in but have it on "value charge" where it won't start charging until later.  I always assumed it would come on if the battery was too hot and it wanted to cool down.