There are many types of lithium batteries, with 18650 and 21700 cylindrical batteries being the most widely used. Today, we will compare the advantages and disadvantages of these two lithium batteries in detail to help you choose the most suitable one.

18650 Lithium Battery

Lower Safety Factor: Mainly used in original factory batteries, with a discharge current of 25-35A. Exceeding this range will significantly increase power consumption.

Applications: Commonly used in lightweight scooters, such as those with 48V 12A-18A configurations.

21700 Lithium Battery

Volume and Capacity Advantages: Compared to 18650, 21700 cells are larger in size and have a higher capacity.

High Discharge Power: Supports a higher discharge power, with a maximum of up to 110A.

Flexible Assembly: Battery packs of the same volume can accommodate larger-capacity batteries.

Advantages: Compact size, no expansion issues, and widely adopted by high-end electric vehicles such as Tesla.

The overall size of the 21700 battery is larger than that of the 18650. With an increased single-cell capacity, the energy density per unit battery is higher. As a result, for the same energy requirement, the number of battery cells needed can be reduced by approximately one-third, which in turn lowers the weight of the battery pack.

The 21700 battery retains the high reliability and stable performance of the 18650 battery while offering significant performance improvements in multiple aspects. Furthermore, compared to other battery models, the selection of raw materials, manufacturing process, and technical procedures of the 21700 battery are similar to those of the well-established 18650 battery. This means that most 18650 production lines can also be adapted for 21700 battery manufacturing.

18650 battery, as cylindrical battery, was initially adopted by Tesla’s early vehicle models due to its mature technology, relatively high energy density, and stable quality control. However, with continuous advancements in battery technology and evolving market demands, the limitations of the 18650 battery have become more apparent. In contrast, the 21700 battery has a larger size, allowing for greater energy capacity. This means that within the same space, a 21700 battery can store more energy.