Understanding Fast Charging on QI Wireless Chargers for Cell Phones
The charging capacity of a cell phone largely depends on its internal circuitry, with the charger existing solely as an energy adaptor. Therefore, providing a charger that matches your phone's maximum power capability is essential. For instance, if your phone supports fast charging at 45W, using an adapter of 90W will still fast charge at 45W. Conversely, using a 10W adapter on the first-generation QI chargers will charge at the strictest rate of 10W. The rule of thumb is that the phone and adapter work at the lowest power available.
As of my current knowledge, there is no standardized low limit for fast charging. Hence, a phone that supports more than 10W on QI mats or 15W on adapters can be considered as a fast charger. Fast charging originated with 15W, and while this is still classified as 'fast charging', newer standards have raised the bar significantly.
Challenges of Wireless Charging
Wireless charging, though convenient, often suffers from a significant drawback: heat generation. The problem with wireless chargers is that they tend to generate more heat compared to wired chargers. This excess heat can lead to reduced battery lifespan and performance issues. The heat generation is even more pronounced in older QI chargers, which are less efficient than their modern counterparts. Modern QI chargers, however, have improved efficiency and can transmit power more effectively.
The Definition of Fast Charging
Fast charging is often an ambiguous term with no concrete definition. It typically applies when a manufacturer enhances the battery to one that can be charged more quickly compared to its predecessors. For example, lithium-ion batteries, which have been around for approximately 15 years, started with a 1C charge rate. This gradually improved over time. About 7 to 8 years ago, they introduced 'fast' charging at a 2C rate. Around 4 years later, they upgraded to a 4C rate, and since this time, the term 'fast' has been abandoned as it has become devoid of meaning.
For me, any charger that can charge my phone at a rate faster than 1C is considered 'fast-charging.' This definition aligns with wider usage, where anything detected above the standard charge rate is recognized as fast charging.
Popular QI Fast Chargers
Existing QI wireless chargers often come with power blocks ranging from 15 to 20W. A cursory look on Amazon supports these ratings, indicating that the majority of users are satisfied with these charging solutions.
Keyword: Fast Charging, QI Wireless Charger, Cell Phone Charging