To know the answer to that question, we need to know a little more about the personalities of batteries like Lithium Ion or Lithium Polymer battery. These are the same exact types of batteries commonly found in your mobile phones.
Here we are going to discuss the most common questions that comes to our mind about batteries, How to make the batteries last longer per charge? How to prolong their lifespan? How to prevent having batteries explode in my face?
While we kno9w that the most convenient tool now a days is the internet to look for all these kind of questions. Its is quite common to say that there are simply too many misconceptions about your smartphone batteries floating around on the internet. No, thanks to the fact that Lithium Ion/Polymer batteries behave very differently from their predecessors, the Nickel metal hydride batteries that have graced the phones of yesterday years.
Back to the topic at hand. Should you charge your phone overnight? To answer that, let’s look at summary of Li battery characteristics:
- Li batteries are afraid of heat. The higher the temperature, the faster it loses capacity over time.
- Li batteries are afraid of being empty. The emptier it is, the faster it loses capacity over time.
- Li batteries are afraid of being full. The fuller it is, the faster it loses capacity over time.
- Li batteries are afraid of being overcharged (charged more than full) or short circuited. If it gets charged too much, it gets bloated due to chemical reactions in the cell.
- Li batteries are afraid of being over-discharged (use more energy than the battery is willing to give). If it gets discharged too much, it gets bloated due to chemical reactions in the cell.
- Li batteries are afraid of being ruptured. If the internals are exposed to air, it catches fire and burn.
- Li batteries keep the scores well. If you charge from 50% to 100% twice, that is considered one charge cycle, not 2.
Expecting more? Nope, that’s all you need to know.
So overnight charging. Is it good or bad?
Let’s talk about safety first. Overnight charging is generally safe as long as your battery, charger and mobile phone are all from reputable manufacturers. Badly manufactured chargers and mobile phones may have overcharge protection circuit that fails, cause your battery to get over charged. When you battery gets overcharged, the internal cell undergoes a chemical reaction, and the battery start to bloat.
If the bloat is too much, the battery ruptures, causing the internals to be exposed to air, resulting in fire and explosion.
While this is still O.K. if you are around and can swiftly put out the fire or prevent the fire from spreading, leaving your smart phone to charge unattended isn’t safe.