The cylindrical AA and 18650 batteries share similarities in appearance and functionality in some ways but they are quite different in many ways. Consumers inquire about their interchangeability to facilitate finding replacements. However, distinctions exist such as their size, the chemical composition, voltage, capacity, and charging/discharging features.
Comparatively, 18650 batteries are larger in size than standard AA alkaline batteries and possess approximately twice the normal voltage. Additionally, 18650 batteries tend to be more expensive compared to AA batteries. In this article, we will explain the two batteries in detail, their difference, uses, and popularity. Without further Ado, let’s started.
What is 18650 Battery?
The 18650 battery is approximately 18 by 65 millimeters in size. It could be slightly larger than a small battery. The voltage range is from 3.2 to 37, and the power capacity is approximately between 1800 and 3500 milliamps. We use the 18650 battery with the BMS to make sure it doesn’t charge or discharge too much.
Additionally, 18650 cells also undergo changes in the physical form of the positive anode. Some batteries have a flat end, while others have a sharp end. Furthermore, the 18650 battery doesn’t have a memory feature, so it can be charged and used whenever without needing to be completely charged.
Experts advise against using 18650 batteries instead of AA batteries. Changing these batteries can be hard because they come in different sizes and have different amounts of electrical power. Deciding whether the 18650 or AA battery is best for you depends on where you plan to use it. The 18650 batteries are excellent for powering devices such as laptops, cameras, and spotlights. If you use your batteries as intended and charge them correctly, they will last a long time and continue to work well.
Why People Like 18650 Batteries
18650 batteries are called giants because they are 18mm wide and 65mm tall. In simple words, it has a giant size more than the AA size of the battery. All 18650 batteries can be charged up and are made of lithium. The main reason why 18650 batteries are very popular is because you can charge them up to 4,000 times. Also, 18650 batteries are reliable and can be used for many different things like flashlights, thermometers, some electric cars, medical equipment, and many more.
What is AA Battery?
AA batteries are smaller than 18650 batteries. They are about 14 by 50 millimeters in size. The regular AA battery usually has a voltage of 1.5. The estimated control range is between 1800 and 2700 milliampere-hours.
However, rechargeable and non-rechargeable AA batteries are different from each other in terms of their makeup and features. Nowadays, you can find AA batteries that can be recharged, just like the ones made from Li-ion, NiMH, or NiCd. But the regular AA batteries that people usually say cannot be charged.
Usage of AA VS 18650 Batteries
These special Lithium batteries are made for devices and equipment that need precise control, like high-tech cameras, handheld remote controls, and electric tools. Please remember that lithium-AA batteries and lithium-ion batteries are different. The last mentioned refers to batteries that can be charged again and again. These batteries are often used in tablets, phones, and drones.
AA batteries called Antacids are used in small electronic devices that need less power. These are small extra lights, small focused lights, controls that are hard to reach, small toys, and small clocks on the wall, among other things.
Many people believe that AA batteries cannot be recharged. However, there have been developments in the market that have made it possible to create AA batteries that can be recharged. The most common type is the NiMH battery, which is more powerful and has fewer harmful metals. Let’s go through the differences between the two in detail.
Differences Between 18650 Battery vs AA Battery
Difference in Dimension
In case you see them, you’ll be able to clearly see that 18650 batteries and AA batteries are diverse in size and dimensions. The 18650 lithium battery is 18mm wide and 65mm long. AA batteries, too called 14500 batteries, are littler than other batteries. They are 14mm wide and 50mm long. So, 18650 batteries are greater and more extensive than AA batteries.
Difference in Chemistry
The 18650 battery could be a type of rechargeable lithium-ion battery that comes in a particular measure. Ordinarily made of lithium press phosphate or a blend of nickel, cobalt, and manganese. AA batteries can be diverse sorts like antacid batteries, zinc-carbon batteries, nickel-cadmium batteries, nickel-metal hydride batteries (NiMH), and lithium-ion batteries.
Size Difference
Cylindrical lithium batteries, like the 18650 battery, are named after their dimensions. The battery’s width is indicated by the number “18” and its length by the number “65.” Although there may be slight variations in the manufacturing process, the measurements generally align closely with the intended specifications.
AA batteries, measuring around 14.5mm in width and approximately 50.5mm in length, may remind you of their use in devices like the Gameboy Colour or TV remote. These batteries were inserted into a section equipped with a spring to securely hold them in place. This design allowed for some flexibility in size, meaning that it didn’t matter if the batteries were a few millimeters larger or smaller.
Difference in Voltage
18650 and AA batteries differ in terms of electricity power. An 18650 battery has a voltage of 3.7 volts, while an AA battery has a voltage of 1.5 volts. Their electrical power levels vary as a result.
Difference in Capacity
Currently, the capacity of an 18650 battery ranges from 1800 to 3500mAh, while an AA lithium-ion battery can hold between 1700 and 2700mAh, and an alkaline AA battery can hold 600 to 2700mAh.
Difference in performance
In general, the 18650 battery has a higher energy storage capacity, which allows it to last longer after being fully charged . However, AA batteries have a shorter lifespan and cannot be recharged, making them single-use only.
Difference in Energy Density
Energy density is a crucial measure for evaluating a battery’s energy storage capability. Higher energy density indicates that the battery can store more energy, resulting in a longer lifespan before requiring recharging or replacement. To calculate how long a battery will last, a simple equation can be used to determine its watt hours. This involves multiplying the mAh number by the voltage and then dividing by 1000.
Now, let’s consider two practical scenarios. For instance, if you purchase a standard AA Alkaline battery from a reputable store like Duracell, it typically has a milliampere-hour (mAh) rating of approximately 1500 and a voltage of 1.5V, as stated in official Duracell information. By multiplying the mAh rating (1500) by the voltage (1.5), the result is 2250. Dividing this by 1000 yields a result of 2.25.
Brief Overview Chart
| Attribute | 18650 Battery Specification | AA Battery Specification |
| Size or Dimensions | 18mm x 65mm | 14.4mm x 50.5mm |
| Power Capacity | 1,500 mAh to 3,600 mAh | 3,000 mAh to 3,500 mAh |
| Performance | Can control gadgets for long time | Control gadgets for short time |
| Voltage (Nominal) | 3.7V | 1.5V(Common)/1.2V |
| Application | Cameras, Flashlights, power banks, laptops, electric vehicles, etc. | Ideal for high-drain remote applications such as electric tools, thermometers, etc. |
Conclusive Remarks
Choosing between an 18650 battery and an AA battery can be challenging due to the complexity of the subject. The popularity of 18650 batteries primarily stems from their ability to be recharged multiple times, up to 4000 times or more, if used correctly. AA batteries come in four main types: Li-ion, zinc-carbon, alkaline, and nickel-based. Among these, Li-ion AA batteries are the most powerful. In terms of capacity, the largest 18650 battery can hold 3,600 milliamp hours of energy, while a lithium-ion AA battery can hold up to 3,500 mAh of power. When comparing the physical sizes, the 18650 battery is slightly larger, measuring at 18mm x 65mm, whereas the AA battery is smaller, measuring at 14.5mm x 50.5mm. This size difference contributes to the 18650 battery’s increased capacity.
In addition to comparing AA batteries, there is also a growing interest in understanding the dissimilarities between 18650 batteries and 4680 batteries, which are considered more advanced and larger in size. Our website offers a simplified explanation that highlights the disparities between these two types of cylindrical batteries, aiding in your comprehension and comparison of them.