What is "BET surface area" and how does it affect the performance of a battery?

BET (Brunauer, Emmett and Teller) surface area calculations are very important in the battery industry. The theory may sound complicated, but in practice its application is quite straightforward and easy to comprehend. An understanding of what the calculations are based on and the experimental parameters utilized in these calculations can aid the battery producer to make a product that is especially suited to the job at hand. It can also prove useful in helping reduce the costs caused by some production errors.