Updated July 2026.
The most visible difference between Qi2 25W and the first generation of Qi2 is power: compatible certified products move from a 15W magnetic profile to as much as 25W. For product teams, the less visible differences are just as important. More power affects the adapter, cable, PCB, coil, ferrite, enclosure and thermal control, while certification remains tied to the exact finished configuration.
Version timeline in plain language
- Qi 1.x: established broad inductive-charging interoperability, including basic and extended power use cases.
- Qi v2.0 / Qi2: launched in 2023 and introduced the Magnetic Power Profile for repeatable magnetic alignment and 15W charging.
- Qi v2.2.1 / Qi2 25W: launched in July 2025 and raised the magnetic charging target to 25W for compatible products.
The WPC now lists v2.3 as the latest specification available to members. That does not make every older certified product obsolete. Products in the field still operate across multiple profiles, so compatibility decisions should be based on the intended devices and certified records rather than a version number alone.
Alignment: from user judgement to a defined magnetic position
Earlier charging pads often depended on the user placing a phone over an invisible coil. Multi-coil pads widened the usable area, but they also added cost, loss and control complexity. Qi2’s magnetic approach gives the device a repeatable position. This can improve usability and reduce misalignment losses when the mechanical implementation is correct.
It does not remove mechanical design work. Magnet location, coil center, ferrite, case thickness and camera clearance still have to be designed as one stack. Accessories that add metal or move the phone away from the coil can reduce performance.
Power: 15W to 25W is a system change
At 25W, the input source and heat path need more attention. Product labels should state the required adapter profile. Validation should measure sustained power and surface temperature, not only the maximum value seen during the first minute.
For an OEM charger embedded in furniture, a car console or medical accessory, ambient temperature and ventilation may differ significantly from a retail desktop stand. The same transmitter electronics can require a different power limit or mechanical solution in each enclosure.
Interoperability: build a real device matrix
Qi2 25W does not mean every phone receives 25W. The transmitter and receiver negotiate an available mode, and the device may reduce power because of battery state, temperature, software or case conditions. A useful compatibility table names the phone model and expected charging profile under a defined test setup.
Certification: version language is not proof
A supplier may have a design based on a v2.2.1 controller, a certified subsystem, or a finished Qi2 25W certified product. Those are different commercial states. Ask for the Qi ID of the exact model and verify it in the public WPC database. If the database record is pending, product copy should say so plainly.
Changes to the coil, magnets, firmware, PCB layout or enclosure may affect the certified configuration. Agree on change control before production, particularly when an ODM design is being adapted for several brands.
Which path is right for a new product?
Choose 15W Qi2 when it meets the device, charging-time, cost and thermal requirements. Choose Qi2 25W when compatible-device speed is commercially important and the enclosure and input system can support it. Use a custom non-magnetic TX/RX solution when the product is not a phone accessory and its geometry, distance, output or host interface does not fit the standard magnetic use case.
CowinLink develops finished chargers as well as embedded TX and RX solutions. Send your device list, mechanical stack, power input and certification objective through the project inquiry page for a feasibility review.
Primary reference: Wireless Power Consortium—Qi wireless charging.
