文档介绍：无线充电详解
——英文版
Theory
advantage: safe, durable, convenient
disadvantage: low efficiency, high cost, unstable, limited distance
ic Induction
(电磁感应)
ic Resonance
(电磁共振)
Radio Reception
(无线电波)
Capacitive coupling
(电场耦合)
Transmission power
1-10W
KW
>100mW
1-10W
Transmission distance
1mm-10cm
1cm-10m
>10m
1mm-10cm
Efficiency
80%
50%
38%
70-80%
Application
Smart phone; Tablet
Automobile
less
less
Theory
Theory
Efficiency
Wireless charging efficiency:45%~82%
Standard
Qi standard——WPC(Wireless Power Consortium) :
Qi passes the benefits of both inductive and resonant charging technologies in a versatile standard. Qi products are incorporating both to offer the innovative services and features in the most energy-efficient and cost-effective possible.
Most of the smart phone wireless chargers are using Qi standard.
PMA standard——Power Matters Alliance:
Focus on inductive charging.
Rezence standard——A4WP (Alliance for Wireless Power) :
Base on the principles of ic resonance.
On June 1, 2015,  A4WP and  PMA, have announced the signing of the merger agreement between the anizations. The transaction establishes a core charging standard supporting a wide range of consumer, medical, military and industrial applications.
Product
Brand: Incipio Ghost——80USD
Type: 220
Input: DC 5V, 4A
Output: 5V,
Size: 89mmx178mmx15mm
Charges 2 patible devices and an extra device via USB
Integrated USB charging port (charges a third device)
Brand: Patriot Memory——20USD
Type: Induction Charger
Input: DC 5V
Output: 5V, 1A
Size:
Patriot Fuel iON ic Charging Pad
Product
Brand: RAVPower——40USD
Input: DC 5V,
Output: 5V, 1A
Size: 145mmx79mmx11mm
Color:black、white
RP-WCN11: Built in 4800mAh battery patible with any QI-enabled LED light display charging indicator
Product