Does more mAh always mean longer battery life?

Batteries are convenient energy sources that power portable electronic devices. From smartwatches to cars, batteries play such an important role in our daily lives that living without them would be almost impossible. If you’ve ever checked the specs of a smartphone, you’ve probably noticed that the batteries have a mAh rating. mAh stands for milliampere-hour, which is a unit of electrical charge. But does more mAh always mean longer battery life?

Does more mAh always mean longer battery life?

Electricity, as we know it, is the result of the movement of electrons from one point to another. The rate at which these electrons flow through a surface is called electrical current and is measured in amps.

When a set of charged particles passes through a circuit in one second, an electrical current of one ampere is obtained.

Batteries generate electricity by moving electrons from one electrode to the other. When a battery moves a set of electrons from one side to the other per second, it generates an electrical current of one ampere.

When you know this, it’s easy to guess that the higher the current or ampere of a battery, the more electrons it can send through your device in a given period of time. However, while this phrase is true, there is more at stake than just the chain.

What does mAh measure?

mAh stands for milliampere-hours, a unit of measurement of charge or electricity. In a nutshell, “milli” is a prefix that means thousandth, so one milliampere is equal to 0.001 amps. The suffix “hour” means that the current is multiplied by one hour, a unit of time.

In batteries, mAh is a measure of the battery’s capacity and uses the three concepts (electrical charge, current and time) to estimate the amount of electricity the battery can hold. For example, a capacity rating of 1,000mAh on a battery means that, once fully charged, it can sustain an electrical flow of 1,000mA for one hour.

It is important to know that this does not mean that a 1,000mAh battery provides a constant current of 1,000 milliamps. If that were true, all batteries would last exactly one hour. The electrical current that a battery provides depends on its applications and the structure of the cell.

For example, an alkaline battery inside a watch will last much longer than the same battery inside a gaming mouse, despite providing the same voltage and having the same capacity.

Another important disambiguation is between the capacity of a battery and the maximum electrical current it can produce. The maximum electrical current that a battery can produce depends on the cell’s structure and is measured as the discharge rate. This is particularly relevant in the case of LiPO batteries, as different LiPo batteries have different discharge values.

A 5,000mAh LiPo battery with a discharge rating of 3 can produce an electrical current of 15,000mA or 15A and naturally this 15A current will last for much less than an hour.

Does more mAh mean longer battery life?

After all this talk about batteries and electrical currents, it’s time to answer the most important question. Does a higher mAh rating mean longer battery life? Well… it depends.

Battery life, or the rate at which a battery discharges during use, depends on both the battery and the device it is powering. So, generally speaking, if you place two identical batteries that only differ in their capacity in two identical devices with the same use, then the battery with more capacity will naturally last longer.

A real example is a watch, where the battery consumption is the same. In this case, a 2200mAh alkaline battery will keep the watch running much longer than a 900mAh one.

Another use case for mAh is in smartphone batteries. Battery capacity is a critical part of a smartphone’s specifications, but a larger battery in a smartphone doesn’t necessarily mean it will have longer battery life.

Many variables affect battery life

However, the capacity of a battery is often measured in mAh or milliampere-hours. This is a measure of how much constant current the battery can provide in an hour before running out.

Many factors, such as structure, voltage and application, come into play to determine the lifespan of a battery. However, if two batteries are identical in all aspects except mAh rating, the battery with the higher mAh will certainly last longer.