Charging our phones should be one of the easiest and most simplest tasks in the world. It's the end of the day and you're just doing the last bit of browsing on your phone before falling asleep. The battery is slowly draining to empty and you know you'll need it on full power tomorrow. So, you plug it into your charger, leave it by your bedside table and wait until the following morning to see a satisfying 100 per cent battery. However, according to Cadex, this is not the best way to charge your phone. The company, that offers devices that test smartphone batteries, runs its own Battery University website which gives some useful tips on how to keep your smartphone's battery healthy. First spotted by Business Insider, Battery University warns that charging your phone to 100 per cent or overnight is not the best course of action. Here's a list of tips of how best to charge your phone Keep the battery between 65 per cent and 75 per cent As tempting as seeing a fully battery block in the top right hand side of your phone is, it's apparently not the best course of action. According to Battery University, the lithium-ion battery in your smartphone will last longest if you keep it between 65 per cent and 75 per cent charged at all times. Don't wear the battery down It can be very difficult to avoid, but running your phone down until the final drops of battery remain is also bad move. Battery University says this deep discharge will wear down the battery. Don't charge your phone to 100 per cent This will be one which could wrangle with a lot of phone users but, according to the experts, doing this can reduce its capacity and shorten its lifespan. Modern lithium-ion batteries do 'not need to be fully charged, nor is it desirable to do so'. Actually, it's better not to do this because a high voltage 'stresses the battery' and will eventually wear it out. Charge it little and often This means avoiding charging it overnight, a golden rule for most people. Charging your phone overnight will apparently cause the most damage to a phone battery's lifespan. Instead, Battery University advise plugging it in whenever you can even it is only for a few minutes. Finally, unplug your phone once it's charged.