The definition of a 21700 battery, specifically a cylindrical battery with an outside diameter of 21mm and a height of 70.0mm. This model is now used by companies in several countries, including Korea, China and the USA.
The 21700 battery was first developed by Panasonic for the US company Tesla. At an investor meeting on 4 January 2017, Tesla announced the start of mass production of the new 21700 battery, jointly developed with Panasonic, which will be produced at Tesla Motors Gigafactory plant. Tesla CEO Elon Musk said that the 21700 type battery has the highest energy density and lowest cost battery in the world, and will be sold at a more affordable price. It can be said that the Tesla Model 3 fully enables the 21700 battery, opening a new phase of cylindrical batteries to improve capacity.
#1-What Are the Advantages of 21700 Batteries?
1.Lighter Weight, More Space for the Whole Car
The energy of a single cell is relatively high, so the number of battery cells required for the same energy can be reduced by 1/3, while greatly reducing the difficulty of system management will also reduce the number of metal structures and related accessories used in the battery, which further strengthens the weight of the lithium battery.
2.Better Cost Performance
With the 21700, the number of battery cells will be significantly reduced. The cost of Tesla’s Pack project accounts for approximately 24% of the total system project cost, and it is expected that the cost reduction of the battery pack project is relatively optimistic.
3.the Battery Energy Ratio Increased Significantly
In 2020, the power battery monomer energy ratio should be overcome three hundred watts per hour/kg, and the power battery system energy ratio should reach two hundred and sixty watts per hour/kg. At present, the best 18650 batteries do not meet this technical requirement, the majority of domestic batteries are in the relative density of one hundred to one hundred and fifty watts per hour / kg each other.
The 21700 type battery has a higher energy density than the 18650 battery, and the number of individual cells can be significantly reduced in use, and the cost will be lower after the group is formed. Energy ratios is up to 300 watts per hour/kg per cell
For example, the 21700 battery system installed in Tesla’s Model 3 has an energy density of around 300Wh/kg, which is more than 20% higher than the energy density of the 18650 battery used in the original Model S. The capacity of the single cell is increased by 35% and the system cost is reduced by around 9%. From the very beginning, the huge advantages of 21700 have sparked widespread interest and research in the industry.
As you can imagine, while an 18650 battery has a capacity of around 2600-3600 mAh, a 21700 battery supports more than 4000 mAh, and there is now a 21700 5000 mAh on the market. while the larger capacity is more conducive to extending the life of modern devices.
4.Fast Charging Speed
Valta’s 21700 battery can be fully charged in six minutes. Other comparable batteries on the market cannot achieve this speed. There is a huge market segment in the automotive sector that has an urgent need for such power and fast-charging batteries and will eventually lead us to electric mobility.
#2-What Are the 21700 Battery Applications?
21700 battery with its advantages in energy density, the future market applications will be very broad. In particular, the application of new energy vehicles is becoming more and more widespread.
The 21700 battery can also be used in 48-volt hybrid systems as a booster to speed up the decarbonisation process of the car.
The 21700 battery is particularly suitable for new concept cars in the premium and sports vehicle market. Its small size makes efficient use of space and provides more power to accelerate the car, plus it can be charged quickly while driving, making the car lighter and requiring less energy.
The 21700 battery is set for a period of growth in the future. In addition to new energy vehicles, 21700 is starting to be used in chargers, e-cigarettes, torches, handheld heads and other devices.