Benefits of Aluminium Cell Housings for Cylindrical Lithium-ion Batteries

A 4680 cell concept The battery industry is targeting larger cell formats, which enable simplified module design and cell-to-pack or even cell-to-chassis solutions. In this regard, hard case battery cells and in particular cylindrical cells will play an important role in enabling the named developments. Tesla’s announcement of a tabless 4680 cylindrical LIB has triggered … Read more

Cylindrical Cell Electrode Estimation

Cylindrical Cell Electrode Estimation: An alternative geometric approach. Here we present a simple method for estimating electrode length in a cylindrical cell. The method is equally applicable to other formats since we make an estimation of the total active electrode area. Results require knowledge of one electrode Active Material (AM) chemistry, electrode porosity and thickness … Read more

Cylindrical Cell Electrode Estimation

Using some simple mathematics and dimensions we can do some cylindrical cell electrode estimation. Knowing the outer and inner diameter of the spiral along with it’s thickness we can calculate the length of the material to create it. D is the inner diameter of the cylindrical can. The inner diameter is that of the mandrel … Read more

Cell Electrode Pressure

The cell electrode pressure is required to keep the cell operating at it’s peak performance over it’s lifetime. However, is there an optimum pressure and why exactly does the cell need it? As the cell is charged lithium ions move into the graphite anode and the cell will increase in thickness. Silicon in the anode … Read more

Tesla 4680 Cell

Tesla 4680

The Tesla 4680 cell has intrigued ever since it was announced. A cylindrical cell that is 46mm in diameter and 80mm high. Estimated Specifications: Capacity tests [6]: Capacity: 23.35Ah at 2.5A discharge ~C/10 Capacity: 20Ah at 25A discharge ~1C 26.5Ah (estimate based on 21700 5Ah volumetric energy density) and this fits with capacity of the … Read more

Cells in Parallel

resistance in busbar joints

When connecting cells in parallel all of the negative terminals are connected together and all of the positive terminals are connected together. The capacity of the parallel group is the sum of the capacity of the cells. Hence three 5Ah cells connected in parallel will give a total capacity of 15Ah. 3 cells connected in … Read more

Function of the Cell Can or Enclosure

cell enclosure functions

The function of the cell can or enclosure is to contain the chemistry over the lifetime of the battery cell and to allow the electrical, mechanical and thermal connections. It must also work in the extremes and have a controlled failure mode. The main cell formats are: coin, cylindrical, pouch and prismatic. The main functions … Read more

Cell Sample Maturity

A B C D Sample development

Cell Sample Maturity is normally defined by the A, B, C, D sample definitions. These stages of the cell design, production line development and material supply are key to the relationship between the cell manufacturer and cell customer. The customer needs to have confidence in the cell design, robustness and quality and this is only … Read more