Just like humans, lithium-ion battery packs don’t like extremes of temperature, which is why automakers often build plug-in cars with liquid-cooled battery packs.
Unlike the 2012 Chevrolet Volt and 2012 Tesla Model S however, the Nissan Leaf doesn't have any liquid cooling for its battery pack, meaning it can overheat when the weather gets too hot.
As owners in the hottest parts of America have discovered this summer, prolonged exposure to heat over 100 degrees Fahrenheit can prematurely age the Leaf’s battery, reducing its capacity and useable range.
There is, however hope.
By reducing your car’s exposure to extreme heat, as well as limiting the amount of heat generated within the battery pack, you can reduce the effect hot summer days have on your Leaf’s battery pack.
Avoid ‘100 percent’ charges
Just like many other Lithium-ion battery packs, the battery pack in the 2011/12 Nissan Leaf does not like to be fully charged, or fully discharged.
As a battery is charged up, its internal resistance increases, making it harder to put more energy into the battery.
2011 Nissan LEAF iPhone App
2011 Nissan LEAF iPhone AppEnlarge Photo
The harder it is to charge, the more heat is generated in the process, raising the temperature of the battery.
Although a 100 percent charge on the Nissan Leaf doesn’t really charge its battery pack to 100 percent -- more like 95 percent -- it still puts the battery pack under more strain than an 80 percent charge.
In hot weather, using an 80 percent charge can significantly improve battery health.
Don’t run your car until empty
Running a battery to almost flat also impacts on battery life and health.
Because power is a function of current times voltage, and a discharged battery has a lower voltage than a fully charged one, an almost-empty battery has to provide a higher current for a given power level than it did when fully charged.
Top Gear Stage Another Electric Car Stunt
Top Gear Stage Another Electric Car StuntEnlarge Photo
Increasing the current drain on the almost-empty battery generates more heat, raising the temperature of the battery.
Reduce power consumption
The more instantaneous energy you pull from your Leaf’s battery pack, the harder it has to work and the hotter it will get.
On hot days, resist the temptation to drive hard and fast. Instead, make sure you accelerate smoothly and calmly, draining as little energy from the battery pack as possible.
In really hot weather, you’ll of course want to use the air conditioning, but wherever possible, pre-cool your car when it is plugged into the charging station before you set off. Not only will it pre-cool the cabin, but it will dramatically reduce the strain on the battery pack.