Before answering this question, we first need to understand what a 18650 cell and an AA cell are.
What is a 18650 cell?
- The 18650 cell is the precursor of lithium-ion batteries. It is a standardized lithium-ion battery model initially established by the Japanese company SONY to reduce costs. The “18” indicates its diameter, which is 18mm, “65” represents its length, which is 65mm, and “0” signifies that it is a cylindrical battery. 18650 cells typically have capacities ranging from 1500mAh to 3600mAh, with a voltage of around 3.5 to 4.0V, and the most common voltage is 3.7V.
· What is an AA cell?
An AA cell is a common type of dry cell battery with dimensions of 14 millimeters in diameter and 50 millimeters in height. AA cells are also known as LR6 batteries and are typically alkaline batteries. They are commonly used in small household electronics, toys, flashlights, and other similar devices. The capacity of AA cells typically ranges from 1500mAh to 2700mAh, and they have a voltage of 1.5V (non-rechargeable) or 1.2V (rechargeable).
·Advantages and disadvantages of 18650 batteries and AA
18650 | AA | |
advantage | long life | cheap price |
High security | Easy to use | |
no memory effect | Environmental friendly | |
shortcoming | The volume has been fixed | The battery is unstable |
High production conditions are required | Short service life | |
| Not suitable for high power equipment |
The 18650 battery cell has a long service life. In normal use, the cycle life of 3.7V 18650 can reach 500 to 1,000 times, and the cycle life of 3.2V 18650 can reach more than 2,000 times. 18650 battery cells are safer than other batteries. It will not explode or burn; the 18650 battery cell has no memory effect, so there is no need to drain the remaining power before charging, making it easy to use.
But the biggest disadvantage of the 18650 battery cell is that its size has been fixed, and it is not well positioned when installed in some products. The production conditions of 18650 batteries are very demanding. Compared with other batteries, the production conditions of 18650 batteries are very high, which undoubtedly increases the production cost.
AA batteries are cheaper than other batteries; AA batteries are smaller and easier to carry and replace; AA batteries are dry batteries that do not contain harmful substances such as mercury and lead and are environmentally friendly.
However, the power of AA batteries will gradually decrease with the increase of use time; the service life of AA batteries is relatively short, and its service life in high-power equipment is even shorter; the output power of AA batteries is relatively low and is not suitable for high-power equipment. Power devices such as camera flashes, etc.
·What is the difference between 18650 battery cell and AA battery?
From the above description, we can know that the obvious differences of 18650 batteries are as follows:
18650 battery cell | AA battery cell |
18mm✖65mm | 14mm✖50mm |
3.5V-4.0V | 1.2V-1.5V |
1500mAh-3600mAh | 1500mAh-2700mAh |
·Can AA replace 18650 batteries?
Can't. As can be seen from the above, the voltage of 18650 battery cells is different from the voltage of AA batteries. Equipment using 18650 battery cells requires high voltage and high capacity rate, so it is not recommended to use AA batteries. 
