What is a 4680 cylindrical lithium battery?The advantages and disadvantages of 4680 battery

4680 Cylinder lithium battery is the battery with a diameter of 46 mm, 80 mm high, cylindrical shape, different from the mainstream square battery, named after the size. It’s batteries made by Tesla, designed to significantly increase range, reduce production costs, and use them in future products such as cyberpickup trucks and semi-freight trucks.

1. The advantages of 4680 battery

1,4680 cylindrical lithium battery is 5.4 times larger than the previous 2170 cylindrical battery, the battery capacity is increased by 5 times, the vehicle range is increased by 16%, the infinite ear design, the charging and discharge speed is increased by 6 times, is expected to reduce the internal resistance of the battery to one fifth of the original, the heat production is lower and safer;

2.4680 cylindrical lithium battery is used with CTC scheme, that is, the battery cell is directly integrated into the chassis to improve the energy density of the battery system, reduce the weight of the vehicle, improve the production efficiency, and have more space for optimization in the ride;

2. The disadvantage of 4680 lithium battery

1. The main disadvantage of 4680 lithium battery is that it is not possible to determine whether it will increase the internal heat dissipation, the expansion of the cell, resulting in the shortening of battery life. The 4680 battery has many advantages, but there are still the following difficulties in production. First, the welding technology of the pole ear is difficult, and the high yield control has threshold; second, the dry electrode process has threshold.

2.4680 cylindrical lithium battery is relatively harsh on the positive and negative electrodes inside the cylinder. Secondly, the difficulty of heat dissipation inside the cell is higher, which has a certain impact on the battery life.

4680 battery is also different from the mainstream battery in cathode materials, the mainstream is mainly graphite, 4680 battery uses silicon-based anode, the material characteristics are higher than capacity, but there are problems such as easy volume expansion, poor electrical conductivity, large first charge and discharge loss. To find a balance between the energy density and the stability, the current practice is to mix silicon and graphite.

4680 In the process, the positive and negative electrode added PVDF coating, using more aluminum foil and copper foil to protect the electrode material, the conductivity is more sensitive. And the infinite ear design, the original positive and negative electrode connection of the glue reduced, cost reduction and efficiency, welding using laser technology.