If you find your auto starter motor turning slower on winter mornings, you are not imagining things. Because batteries feel the cold like us. And like us, this also affects their ability to get going. However, this is not a guarantee issue: it is the effect of nature. If we are golfing at sub-zero temperatures in the morning, we should keep the cart locked up at night.
How Batteries Feel the Cold and Heat
Batteries do not enjoy getting hot and sweaty either. This causes their electrolyte to expand and puts internal pressure on their cases. By now, we know that lithium batteries can overheat and explode. The same may happen to lead-acid batteries when we recharge them incorrectly.
Locking batteries away in a tin shed in the Arizona desert at the height of summer, may cause something similar. They might stop delivering their electricity properly, start expanding, bulge, and in an extreme case burst open. This is bad news if they are in a device.
How Batteries Malfunction in Extreme Temperatures
Batteries change the chemical energy in their terminals to electricity. We call this an electro-chemical reaction. During this process, ions flow between the cathode and the anode.
At normal temperatures, this happens at a speed the manufacturer intended. However, and this is the point, they flow slower when the electrolyte temperature plummets. Batteries feel the cold just like us. If the electrolyte becomes over-heated, the opposite happens.
The ions start zipping across at accelerating rates. This is turn causes more heat in a process we call thermal runaway, and it can happen in circumstances we cannot always predict. However, the most likely cause of auto starter-battery damage is leaving the car in the sun day after day. This normally results in slow degradation and shorter battery life.
However, if you open the hood and notice your battery bulging, do not touch it. Rather close the hood and call an electrician. Similar things can happen to the batteries in your smart watch, laptop, or phone. Thus never take these into a sauna. Leave them outside a chiller room or keep them wrapped up warmly. Batteries feel the cold and the heat, just like us.
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Preview Image: Winter Morning