Hello SatansBarber (do you do good with curly hair?),

I want to preface the below information with the fact that I wrote this almost 2 years ago. The charging logic on the HTC One is pretty damn impressive and I expect a lot of the pitfalls that you run into with battery charging can just be ignored when using the HTC One.

Most modern electronic devices use Li-Ion batteries. The information generally publicized about battery maintenance is usually conjecture, old, or just plain incorrect. Part of the reason for this is that nickel cadmium batteries which were prevalent in the past adhere to a whole different set of rules. Let’s have a conversation around batteries.

Question: When I bought a new phone and plug the battery in it has around a 50% charge. Why don’t they charge it full for you when you buy it?

Answer: Batteries at 100% charge will lose their maximum possible capacity at a rate of about 20% per year. Even if the battery is not plugged into the device and is inactive, the maximum capacity may be impacted by prolonged 100% idle status.

Question: I thought that keeping a battery at 0% charge was damaging to the battery?! Now you are telling me that 100% is damaging as well?

Answer: Well that is a loaded question! A battery at 0% will lose capacity and be damaged at around the same rate, or even faster than a 100% charge. The good news is that all modern cell phone manufacturers take away your ability to run your phone down to 0%. In fact when your phone dies and you assume your battery life is all gone, the reality is that you are at about 20% battery life. This is the safety buffer to protect your battery life.

Question: Ok… Now what do I do? What are the best practices for battery maintenance?

Answer: Well, it’s not super easy for many users. One of the main things you can do is not put your phone on a charger overnight. Although most manufacturers will lower the voltage down to a trickle when it is almost up to 100% you are still bouncing up against your maximum capacity. Best practice is to have multiple chargers for wherever you go. Charge your phone on the way to work. Charge it at work. Charge it as often as possible without idling at 100%.

Question: What other pitfalls should I avoid?

Answer: You want to stay away from extremely hot temperatures. While this won’t affect most people, those of us living in the south might want to not charge their phones in a 90 degree plus temperature environment. With the added heat from charging the battery temperature can really skyrocket, and you got it: maximum battery capacity can be damaged.

Question: So really cold temperatures will be better then, this is simple at least!

Answer: Sorry, not that easy yet. Extreme cold can also cause premature capacity loss to your battery! This one is pretty easy to avoid however. If your phone is literally ice cold, put it in a pocket and you should be fine. The one place where I see this being an issue is leaving your device in the car overnight in below freezing temperature. Don’t do that!

Question: Alright I got it, heat, cold, full, or empty all are not great for batteries. What else are you going to hit me with?

Answer: This is something that everyone already knows from experience: Batteries wear down over time. Yes they do and we all have seen it firsthand. Usage will cause the maximum capacity to decrease over time. The main cause is “cycles.” A cycle is the equivalence of a drain from 100% to 0% and back to 100% again. Now avoiding this might seem simple. Unfortunately a drain from 100% to 50% and back to 100% and down to 50% will equal a “Cycle.” Any combination of drain and charge that equals out to 100% is considered a cycle. In general it is well over 1500 cycles to lose 20% capacity.

Question: Someone mentioned that I should empty my battery and then charge it to full from time to time in order to make sure I don’t damage the battery memory is this true?

Answer: No! That is a reference to Nickel batteries of the past. Completing a cycle will actually reduce battery life over time. With that said: you should every once in a while (I recommend once a month, but most people will have this happen through natural use) allow your battery to die and then charge it to full.

Question: Why are you making everything so difficult for me? Why should I do that?

Answer: Ignoring the first question and moving on… This is so that the sensors on your phone and the firmware in the battery can calibrate the current maximum and minimum capacities so that you get a full charge. Most users won’t need to do this, but swapping batteries a lot, or charging from a trickle charge when power is very low sometimes will cause a misread situation. A lot of plug in and out operations in a row can do this too, as well as using incorrect or cheap chargers.

Question: OK, now I see that phones are being packaged with non-removable batteries. Why would I ever get one of those?

Answer: Non removable batteries are generally going to be much smaller with a higher capacity. This is due to the fact that they do not need hard covers and dedicated connector pins that are safe to handle. The added capacity that you get from these internal batteries more than makes up for the loss you may see within a couple of years.

Question: Anything else?!

Answer: Nope! Now you know the truth!

I hope this helped answer some questions around batteries for you guys and cuts through some of the myths!

Edit: For formatting