What Are High-Rate Batteries and What Is the Role of High-Rate Discharge?

What Are High-Rate Batteries?

Before diving into high-rate lithium batteries, let's first understand the term "rate." The rate generally refers to the discharge rate, which is the current value required for a battery to discharge its rated capacity within a specified time. It is numerically equal to multiples of the battery's rated capacity and is typically represented by the letter C. A high rate means that the battery can discharge at a large current, and a high-rate lithium battery is a type of lithium battery that can discharge at a large current. High-rate batteries usually refer to lithium batteries, where lithium-ion batteries are a type of high-rate rechargeable battery that primarily operates based on the movement of lithium ions between the cathode and anode. During charging and discharging, Li+ ions intercalate and de-intercalate between the two electrodes: during charging, Li+ ions de-intercalate from the cathode and intercalate into the anode through the electrolyte, making the anode lithium-rich; the process is reversed during discharging.

What Is the Role of High-Rate Discharge?

What is the role of high-rate discharge for batteries? High-rate discharge refers to the discharge at a large current, which can be harmful to the battery, leading to high technical and process requirements for battery manufacturers. What is the role of high-rate discharge? This involves the issue of power output of the device. Take drones, which commonly use high-rate batteries, as an example. Drones must overcome their own gravity to do work, thus having high requirements for the net weight of the battery. Increasing the battery volume would also increase the net weight, so only a polymer lithium-ion battery with a lighter net weight under the same volume can meet the requirements. On the other hand, drones have particularly high demands for battery output power. When quickly increasing the throttle from a hover to maximum speed, the battery output power increases rapidly, with a several-fold increase in output power in a short period. At this point, according to the physics formula for electrical power P=UI, with the voltage remaining constant, the only way to increase the output power is by increasing the current. In this way, high-rate discharge can output more power, capable of driving heavier loads or achieving faster speeds.

Edited by Richard