Technical FAQs 4

What is a 21700 battery?

The 21700 battery is a cylindrical lithium-ion battery with a diameter of 21mm and a length of 70mm. It offers a nominal voltage of 3.7V and a capacity of up to 5,000mAh, making it a powerful and efficient energy source. Its energy density ranges between 250 Wh/kg and 300 Wh/kg, depending on the chemistry.

What is a 21700 cell?

For this article we will concentrate on the 21700 format, but this is migrating towards the 46mm diameter 46xx class of cylindrical cells in a push to reduce cell manufacturing costs. The 21700 cell increased the working volume over the 18650 by a factor of >1.4x

Are 21700 batteries safe?

Unprotected 21700 batteries: Lack built-in safety features and are generally used in battery packs with external battery management systems (BMS). 21700 batteries are widely used in: Electric vehicles, with companies like Tesla and other manufacturers using them in battery packs for improved energy storage and performance.

How much does a 21700 cell weigh?

The 21700 cell weighs approximately 60–70 grams, depending on the manufacturer and specific chemistry. While slightly heavier than the 18650 cell, this weight increase is justified by its higher capacity and energy density.

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Cylindrical 21700 battery cell

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21700 Cylindrical Lithium-Ion Battery Cell

The 21700 cylindrical lithium-ion battery cell is a key specification in the lithium-ion battery field. With its balanced performance in capacity, energy density, and power output, it has become a

21700 Cylindrical cells – Comparison of

Feb 12, 2025 · The 21700 cell has been mass-produced lately by many companies who were producing 18650, and some of these companies

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A 21700 battery is a high-capacity, rechargeable lithium-ion cell designed for superior energy efficiency and performance. With a standard size of 21mm in diameter and 70mm in length,

21700 Batteries | Samsung 40T/50E, Molicel

A 21700 battery is a rechargeable lithium-ion cell with a cylindrical shape and standardized dimensions of 21mm in diameter and 70mm in length. It was

Understanding the 21700 Battery and Its

May 17, 2025 · The 21700 battery is a cylindrical lithium-ion battery with a diameter of 21mm and a length of 70mm. It offers a nominal voltage of

Understanding the 21700 Battery and Its Specifications

May 17, 2025 · The 21700 battery is a cylindrical lithium-ion battery with a diameter of 21mm and a length of 70mm. It offers a nominal voltage of 3.7V and a capacity of up to 5,000mAh,

What Are the Key Specifications of the 21700 Cell?

Apr 11, 2025 · The 21700 lithium battery cell has emerged as a pivotal innovation in energy storage solutions. With its 21mm diameter and 70mm length, this cylindrical power source

Global thermal image of cylindrical 21700 Li-ion batteries

Feb 1, 2024 · A cylindrical rechargeable 21700 LIB is utilised here because: (1) this represents one of the most common formats, highlighting the practical value of the global thermal image

21700 Cylindrical cells – Comparison of economical vs

Feb 12, 2025 · The 21700 cell has been mass-produced lately by many companies who were producing 18650, and some of these companies have completely moved to 21700 production.

21700 Cylindrical Lithium-Ion Batteries: Powering the Future

The 21700 cylindrical lithium-ion battery, named for its 21mm diameter and 70mm length, has emerged as a dominant force in modern power solutions. This article delves into the

21700 Batteries | Samsung 40T/50E, Molicel P42A/P45B

A 21700 battery is a rechargeable lithium-ion cell with a cylindrical shape and standardized dimensions of 21mm in diameter and 70mm in length. It was developed as an improvement

21700 Batteries | High-Performance Lithium

A 21700 battery is a high-capacity, rechargeable lithium-ion cell designed for superior energy efficiency and performance. With a standard size of

21700 Cylindrical Cells

The active layers of the cell are wound in a spiral. Normally these cells have the lower case as the negative terminal and the top centre as the positive terminal. However, a number of larger

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