Battery cooling 1

[Rmpadilla98]

HI all,
Someone would know the steps to calculate the amount of air needed to cool this module of a battery made up of batteries.

 

[BrianPetersen]

We have a students forum section, and this really belongs there!

Things you're going to need to know.

What's the instantaneous and longer-term-average charge and discharge rates. How much (a) peak, and (b) longer-term-average are you going to have to deal with?
What's the efficiency of charging and discharging (i.e. the discrepancy between energy fed in and energy that comes out is what shows up as heat)?
How's the thermal mass compare to the heat load (how much can you rely upon thermal mass to soak up heat-load spikes)?
What's the maximum and minimum operating temperature range of the batteries?
What's the maximum and minimum ambient temperature that this is designed to operate in?
If the battery has been stored at a temperature below the design minimum, are you going to need supplementary heating?
Likewise, if the battery temperature reaches the top of the maximum operational temperature range, what are you going to do about it?

I have a Chevy Bolt. It has a nominally 64 kWh lithium-ion battery pack with liquid heating/cooling, its own small coolant pump, a 2 kW electric-resistance battery heater, and it is interconnected with the air-conditioning system in the car (there's an extra evaporator in the coolant loop). Battery heating is only active if the battery-pack temperature is below some minimum which is below 0 C, but I don't know how far below. If left outside in -15 C for long enough without being plugged in, it will complain "Propulsion power reduced" until the battery temperature comes up to the operational minimum (you can still drive, but slower, and charging is REALLY slow). Battery cooling is active when the battery temperature is above 40-something C. It doesn't do anything when the battery pack temperature is above 0ish and below 40ish. Some newer cars have battery pre-conditioning to get the battery temperature into the optimum range before charging, but this one isn't that sophisticated.

The Nissan Leaf used air cooling of the battery - all they did was circulate interior air through the battery, with the presumption that you would have the interior heat on if it was really cold (same condition the battery wants heating) and the air-con on if it was really hot (same condition the battery wants cooling). That car taught the rest of the industry that you really need active thermal management with a liquid coolant. Maybe for a low-powered application used in temperate climates it doesn't matter so much.