Tesla 4680 Battery-Battery Technology Upgrade-Part 1.
1. Definition
The 4680 battery is a new generation cylindrical battery with a diameter of 46mm and a height of 80mm introduced by Tesla.
For batteries, when the energy density is increased, the power density will decrease. The diameter of 46mm is the best choice for a cylindrical battery that takes both high energy density and high power density into consideration.
4680 battery display diagram
1.1. Core innovation
Large battery cell + full pole ear + dry battery technology
1.2. Performance breakthrough
The 4680 battery greatly increases the battery power (6 times that of the 2170 battery), reduces the battery cost (14% to the 2170 battery), optimizes the heat dissipation performance, production efficiency, charging speed, energy density, and cycle performance.
There is room for further improvement.
Cylindrical battery size and performance changes
2. Structural changes
2.1. All pole ears
The 4680 battery has greatly improved battery power, optimized heat dissipation performance, production efficiency, and charging speed through changes in the structure of the tabs.
2.1.1. Full tab structure
Tabs: Metal conductors that lead the cathode and anode from the battery core, and are the contact points during battery charging and discharging. In battery operation, electrons flow from the positive electrode tab to the negative electrode tab.
The flow path is proportional to the internal resistance of the battery, and the flow width is inversely proportional to the internal resistance of the battery.
The internal power loss of the battery is proportional to the square of the internal resistance. The larger the contact area of the tabs and the shorter the tab spacing, the higher the battery output power.
The traditional battery has only two tabs, which are connected to the cathode electrode and the anode electrode. The 4680 battery realizes all tabs (cutting the tabs directly from the cathode electrode/anode electrode), which greatly increases the current path and shortens the distance between the tabs, thus significantly increase the battery power.
……To be continued
