What is an ampere hour?
The ampere hour (Ah) is a unit of electrical charge, a unit of measurement of the maximum amount of energy flowing through terminals, such as a solar battery, for sixty minutes.
This measurement is used by manufacturers to indicate the capacity of a photovoltaic battery when storing electrical energy, both when charging and discharging.
For example, a battery with a capacity of 100 Ah, in perfect conditions according to the manufacturer, would give a current of 100 A for one hour (10 A for 10 hours or 1 A for 100 hours).
Ampere hour equivalents
In the International System, the unit of electric charge is the Columbium (C). One ampere hour is equivalent to 3600 Coulombs (amperes per second). In the case of electrochemical calculations, Faraday's constant is also used, where a charge of 1 mole of electrons is equivalent to 26.8 ampere hours.
To know how much electricity the battery can store, it will be necessary to multiply the Ah by 3600 and by the voltage, which is always fixed. The result expressed in joules will be the amount of electricity.
What do ampere hours indicate?
As mentioned above, ampere hours are used to indicate the capacity of the battery, or any other energy storage device. Sometimes, if the load capacity is low, this capacity can be expressed in milliampere-hours (mAh).
When choosing the battery for its charging and discharging capacity, the speed of the battery must also be taken into account. As the battery is depleted, the internal resistance gradually loses energy.
Importance of Ah when choosing a photovoltaic battery
When we are going to choose a photovoltaic battery for our installation, it is important to take into account the charge and discharge value of the battery. The higher the charge capacity, the more time we will need to "fill" the battery, while the higher the discharge capacity, the longer the battery will be able to deliver energy, always depending on the quantity demanded.
It is therefore important to always have a professional who can advise on the most suitable battery for each type of installation.