TUTORIALS 2989

Match the Battery to the Application to Avoid Disappointment

By: Len Sherman

Abstract: End-customer satisfaction (or dissatisfaction) with portable devices depends largely on battery performance.

The main performance metric for batteries is, of course, battery life. On the surface, this is a simple spec, but in truth it has many dimensions. These include the system's load profile (how much of the time it spends using full load current, a fraction of it, or just microamps); power-supply efficiency; system power management; battery type; and charging methods.

While these performance characteristics are individually important, how they interact can enhance, or diminish, the end-customer’s experience. Generally, if a customer becomes aware of the battery, that is bad! The best products make the battery \"disappear\" with either very infrequent cell replacement (e.g., TV remote controls) or charging, or with unobtrusive charging (e.g., electric toothbrushes). Situations where customers think about batteries as much as the device's function are best avoided.