18650 vs AA Battery: What's the Difference?

What is 18650 batteries？

It is a standard lithium-ion battery model set by Japan’s SONY company in order to save costs. The 18 means a diameter of 18mm, 65 means a length of 65mm, and 0 means a cylindrical battery.

There is a clear difference between the 18650 vs AA battery (No. 5/7 battery) we usually use. 18650 is not any number batteries, but A-type batteries with a diameter of 18mm, which are generally lithium batteries.

What is AA batteries?

There is a clear difference between the 18650 lithium battery and the AA battery (No. 5/7 battery) we usually use.

18650 is not any number batteries, but A-type batteries with a diameter of 18mm, which are generally lithium batteries. AA battery is one of the battery types, and its general size is 14mm in diameter and 49mm in height. The voltage of 18650 lithium battery is generally around 3.5~4.0V, the most common voltage is 3.7V; while the voltage of AA battery is 1.5V (non-rechargeable) or 1.2V (rechargeable).

AA battery is one of the battery types, and its general size is 14mm in diameter and 49mm in height. The voltage of 18650 lithium battery is generally around 3.5~4.0V, the most common voltage is 3.7V; while the voltage of AA battery is 1.5V (non-rechargeable) or 1.2V (rechargeable).

What is the difference between 18650 vs AA batteries?

Different sizes. Although 18650 and AA batteries look alike, the size of the two is actually different. The specification of 18650 lithium battery is 18 mm in diameter and 65 mm in length; while the specification of AA battery (in fact, the scientific name of AA battery is 14500 battery) is 14mm in diameter and 50mm long. 18650 is much larger in length and diameter than AA batteries.
Different voltage. The voltage of lithium batteries is generally around 3.5~4.0V, the most common one is 3.7V; while the voltage of AA batteries is 1.5V (non-rechargeable) or 1.2V (rechargeable).
Its working principle (internal chemical reaction process) is different.
18650 is a rechargeable battery, and most of ordinary AA batteries are disposable batteries, which are rarely rechargeable or cannot be recharged.

18650 vs AA batteries, What are the advantages of 18650 lithium batteries?

Large capacity, The capacity of the 18650 lithium battery is generally between 1200mah and 3600mah, while the general battery capacity is only about 800mah. If combined into a 18650 lithium battery pack, the 18650 lithium battery pack can easily exceed 5000mah.
Longer Service Life
Higher safety performance. 18650 lithium battery has high safety performance, no explosion, no combustion; non-toxic, non-polluting, RoHS trademark certification; all kinds of safety performance in one go, the number of cycles is more than 500 times; high temperature resistance performance, The discharge efficiency reaches 100% under 65℃. In order to prevent the short circuit of the battery, the positive and negative electrodes of the 18650 lithium battery are separated. Therefore, the possibility of short circuit phenomenon has been reduced to the extreme. A protection board can be installed to avoid overcharging and over discharging of the battery, which can also prolong the service life of the battery.
High voltage. The voltage of 18650 lithium batteries is generally 3.6V, 3.8V and 4.2V, which is much higher than the 1.2V voltage of nickel-cadmium and nickel-metal hydride batteries. (click here to learn about NPP High Voltage Battery)
No memory effect. It is no need to empty the remaining power before charging, which is convenient to use.
Little internal resistance
It can be connected in series or in parallel to form a 18650 lithium battery pack
Wide range of use.
- Small equipment: notebook computers, walkie-talkies, portable DVDs, instrumentation, audio equipment, aircraft models, toys, video cameras, digital cameras and other electronic equipment.
- Large equipment: lithium battery backup for home, outdoor energy, tram power, 12v lithium battery / 24v lithium battery for RVs, 36v lithium battery for golf carts, 48v lithium battery for telecom

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