Inductive Charging - Disadvantages

Disadvantages

• Lower efficiency, waste heat - The main disadvantages of inductive charging are its lower efficiency and increased resistive heating in comparison to direct contact. Implementations using lower frequencies or older drive technologies charge more slowly and generate heat within most portable electronics.

• More costly - Inductive charging also requires drive electronics and coils in both device and charger, increasing the complexity and cost of manufacturing.

• Slower charging - due to the lower efficiency, devices can take longer to charge when supplied power is equal.

• Inconvenience - When a mobile device is connected to a cable, it can be freely moved around and operated while charging. In some implementations of inductive charging (such as the Qi standard), the mobile device must be left on a pad, and thus can't be moved around or easily operated while charging.

• Incompatibility - Unlike (for example) a standardized MicroUSB charging connector, there are no de facto standards, potentially leaving a consumer, organization or manufacturer with redundant equipment when a standard emerges.

Newer approaches reduce transfer losses through the use of ultra thin coils, higher frequencies, and optimized drive electronics. This results in more efficient and compact chargers and receivers, facilitating their integration into mobile devices or batteries with minimal changes required. These technologies provide charging times comparable to wired approaches, and they are rapidly finding their way into mobile devices.

For example, the Magne Charge vehicle recharger system employed high-frequency induction to deliver high power at an efficiency of 86% (6.6 kW power delivery from a 7.68 kW power draw).