What 18650 battery to buy-capacity and types?

Batteries have become part and a person of our daily lifestyle as it may be difficult to go one day without using a device that is powered by a cell. From your smartphone, where you'd check for emails, to your watch, where you always look down at to check the time, we are all surrounded by batteries everywhere. One may say that our lives are also technically powered by such cells and which wouldn't be a hoax. Batteries have powered the evolution of technology for decades, if not centuries. 

Lithium-ion has proven to be the most promising battery technology there is and the presence of 18650 batteries can confirm this statement. These cells are but an excellent example of how lithium-ion batteries continue to support life as it is and show that improvements, as well as advancements, can be made. 

What is the largest capacity of 18650 battery?

Lithium-ion 18650 batteries are powerful enough to provide sufficient energy for operating electronic devices with large power requirements such as an LED flashlight. 18650 cells being lithium-ion batteries their available power is typically measured in milliamp-hours (mAh) and the higher this amount, the better the power source. 18650 cells usually provide longer-lasting power and are therefore ranged between 2100 to 3400 mAh. Anything above this should be intensely examined as they can be a fluke in the market looking to sell while endangering lives. 

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Can you use AA batteries instead of 18650?

Some of the standard cells that will be discussed in this guide are the 18650 lithium-ion batteries and AA cells. Many a time people confuse between 18650 batteries and AA cells and often think that they are one of the same. However, these two types of batteries differ in various ways, which are explained in this article. 

Power output

AA batteries tend to have a lower power output as compared to 18650 batteries. Note that 18650 cells are a lithium-ion version and contain a nominal voltage range of 3.6 V per cell. In addition to this, the batteries have a modern design and incorporate original lithium ions joined to specific circuitries. For the AA batteries, some are primary non-rechargeable, while others are rechargeable cells such as the likes of zinc-carbon cells and they operate with about 1.5 V. different types of AA batteries; however, they have different nominal voltages. 

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The nominal voltage of a 18650 battery can, therefore, be said to be double that of an AA cell. This ultimately means that if an electronic device that uses AA cells is incorporated with 18650 batteries instead, then it could lead to damages. Similarly, devices that utilize 18650 batteries cannot be fixed with AA cells because they may require higher loads of energy of which the AA cells may be incapable of coping up with. This could also lead to damage to the cells as well and, therefore, calls for the utmost care to be taken when choosing between the two. 

Size

One can also differentiate between AA batteries and 18650 cells by comparing their sizes. 18650 cells tend to be longer than AA batteries with a length of about 65mm and a diameter of around 18mm. 

Price

Because 18650 batteries provide a more massive power output and are technically bigger in size than AA cells, they are therefore more costly than their AA companions. AA batteries are also a common site in various stores, unlike 18650 batteries, which may only be acquired across a few outlets. 

18650 and AA batteries each have their benefits and limitations. Even though some of these characters may be the same, you should never use AA cells in place of 18650 batteries or vice versa. Some devices utilize AA batteries, while others need 18650 cells. Pick the battery that is suitable and compatible with your device. AA cells are commonly found in flashlights, clocks and other conventional electronics. 

What are the types of 18650 batteries?

There are generally two types of lithium-ion 18650 batteries and them include:

1. Protected 18650 batteries

2. Unprotected 18650 batteries

Protected lithium-ion 18650 cells

When 18650 batteries are said to be protected, they contain a small electronic circuit incorporated into the packaging of the cell. This targeted circuit protects the battery from hazards like overcharging, short circuits, over-discharging, and a high range of temperatures. Protected 18650 batteries are considered safer for use in your devices as compared to unprotected ones because they come incorporated with the following attribute or components:

1. A pressure valve that permanently disables the cells upon detection that the pressure is too high within the cells, which could have been caused by overcharging. 

2. A PTC which protects the cell against overheating and overcharging by automatically resetting the cell. 

3. A PCB that protects the cell against over-discharging, overcharging, or short circuits depending on the design of the cells. This feature will reset automatically whenever the cell is placed into a charger. 

Unprotected 18650 cells

These types of 18650 cells do not contain the unique electronic circuit in its relevant cell packaging. This makes them capable of storing more charge capacity and current as compared to a protected 18650 cell. However, the benefits may be overshadowed by the rampant risks of overheating, short-circuiting, and over-discharging. Unprotected 18650 cells are also more inexpensive to acquire than their protected allies. 

Conclusion

Lithium-ion 18650 cells are a powerful battery technology and should thus be treated with the utmost care when handling them. Never buy a 18650 battery based on the price tag as these cells are costly and the self-proclaimed cheap ones may be a hoax that is capable of damaging your device. If you're on a budget, it would best be wise to consider another alternative or wait for the funds to be available rather than purchasing an off-the-counter standard version of the cell. You must however, decide on whether to settle for the protected or unprotected versions of 18650 cells. It would be best to go for the protected 18650 batteries though because the unprotected ones pose significant risks.