What is mAh (Milliamp Hour): Understanding Battery Capacity
What is mAh (Milliamp Hour): Understanding Battery Capacity
While looking for a battery-powered device, you must have seen the abbreviations like mAh and Ah. And perhaps, "What is this mAh?" is the most common question that beeps into your mind then.
Well. In this fast-paced digital age, our lives significantly rely on batteries. We need them to keep our smart devices alive, our laptops running, and our electric cars working. Under such circumstances, ensuring our devices have enough battery to last a day or two is one of our toughest challenges.
It is exactly where the concept of mAh enters. mAh is a measurement of the battery's capacity. Technically speaking, it defines how many milliamps can be transferred per hour.
This comprehensive guide will demystify everything about mAh and what it stands for on batteries. It will also stipulate three top recommendations for the best battery backups for energy storage.
Fundamentals of Electricity and Battery Technology
Before we delve into mAh and battery capacity, knowing the fundamental principles of electricity and battery technology is crucial. Electricity, in its essence, is the flow of charged particles through a conductor. These charged particles are typically electrons. We harness this flow of electricity to power our electronic devices.
Conversely, batteries are mechanical systems that chemically store electricity and release it when required. When connected to a circuit, a chemical reaction occurs between the battery's electrodes and the electrolyte. This reaction then generates a flow of electrons through the circuit.
Yet there are numerous types of batteries; the most common types used in portable electronic devices are Lithium-ion and LiFePO4. Li-ion batteries come with a high energy density, which implies they can store a lot of energy. Additionally, they are portable and rechargeable. However, they are also costly to make and may be harmful if not handled carefully.
LiFePO4 batteries are a sub-type of Lithium-ion batteries, but they are safer due to strong covalent bonds between iron, phosphate, and oxygen atoms in the cathode. Since they are more stable and immune to thermal runaway and overheating, they are standard in portable power stations and other solar applications.
What is mAh?
Now that you have a fundamental comprehension of battery technology let's dig into the concept of mAh. mAh (milliampere-hour) represents the amount of electrical charge a battery can store.
The mAh is a small unit of measurement, with one mAh equaling one-thousandth of an Ah (ampere-hour). That means a battery with a capacity of 5000mAh can provide 5 amperes of current for an hour, 2.5 amperes for two hours, etc.
Significance of mAh
mAh is the most critical factor when buying any battery-powered device. In other words, it is imperative to check the mAh rating of a battery, as doing so can help comprehend its power storage capacity and how long it can work before depletion.
Typically, a battery with a higher mAh rating has a long lifespan. For example, a solar generator kit equipped with a 3,000 mAh battery will generally last longer than a solar generator with a 2,000 mAh battery. Nevertheless, mAh alone does not tell everything about the performance of a solar generator battery. Other factors, such as inverters, solar panels, and charge controllers, also play a role.
Here, it is worth mentioning that battery life does not follow a linear battery. A battery with double the mAh rating will not guarantee double the lifespan. It may fluctuate based on how you use it. For instance, using your solar generator battery to power a refrigerator or air conditioner will deplete the battery more quickly than powering your mobile phone.
Power Pretty Much Anything, One Hour to Charge, All Day to Power
mAh VS Charge Capacity
Another term usually associated with batteries is their charge capacity. Although both terms indicate the battery capacity or the amount of power a battery can hold, they are used in slightly different contexts.
The term "mAh" commonly describes the battery capacity of portable devices like tablets, mobile phones, and laptops and indicates the energy stored by any battery.
On the contrary, the charge capacity defines the battery capacity of solar storage systems and electric vehicles. This unit measures the energy a battery can receive during a charge cycle. This measurement is typically expressed in kWh (kilowatt-hours) or Wh (watt-hours)
Here’s how mAh and charge capacity are connected.
Wh = mAh*V/1,000
It is evident from this equation that one watt-hour is equal to one milliamp-hour multiplied by voltage divided by one thousand. But this technical equation can be confusing, so let me lead you by an example.
Suppose you have a solar battery with 5,000 mAh. That means it can provide a charge of 5,000 mAh at a specific voltage. If the voltage at which charges are transferred is 5V, the total energy in this example will be 25 watt-hours (5,000mAh*5V/1000 = 25Wh).
What Does mAh Rating Mean?
The mAh rating is the designated storage capacity of the battery. It is the product of a milliampere an hour. Its formula is:
mAH = mA*H
Here is an example to enhance your understanding. Consider a battery rated at 8V AND 2,000mAh. It shows the battery can deliver 8 volts at 100 milliamps for 20 hours (100mA*15H = 1500mAh).
What Does mAh Stand for on Batteries?
Though mAh is a common term used for all batteries. However, the context in which this term is used can vary for different batteries. Below is a brief explanation of the mAh of various batteries.
mAh on A Mobile Battery
The mAh rating is the most appropriate parameter for quantifying the electrical charge a mobile battery can store. You can calculate the backup time of mobile batteries using this formula:
Backup Time = mAh / Current discharged in mA
For instance, if the capacity of your device battery is 2,000 mAh and it consistently draws 200 mA of current, the device would provide backup power for 10 hours (2,000 mAh/200 mA = 10 hours). It means your device has a battery life of 10 hours.
mAh on A Car Battery
The mAh rating on your car's battery shows how long you can drive without recharging. Batteries with higher mAh ratings have larger storage capacities and extended run times. There are numerous types of car batteries, but lithium-ion and lead-acid batteries are the most prevalent.
Lead-acid batteries have an approximate mAh capacity of 135-300 recharge cycles. They have a limited lifespan and must be replaced every 3 to 5 years.
Lithium-ion batteries, on the other hand, have higher mAh and longer battery life. Their mAh ranges from 300 to 400 recharge cycles, and their life exceeds five years.
mAh on A Rechargeable Battery
Unlike disposable batteries, rechargeable batteries can be recharged after they have been depleted. The mAh rating of rechargeable batteries equals that of non-rechargeable batteries.
mAH to Wh Conversion
Next, we will discuss how to convert mAh to Wh. To convert mAh to Wh, multiply the charge and voltage. Then, divide the result by 1000 to get a watt-hour.
The conversion formula from mAh to Wh is:
E (Wh) = Q (mAh)*V/1000
Here, E represents the energy in watt-hours, Q is the milliamp-hour charge, and V is voltage.
Using this formula, let's calculate the watt-hour of a battery with a 1,000 mAh capacity rated at 240 Volts.
E (Wh) = 1000 mAh*240V/1000 = 240Wh
