Qi2 is the current generation of the Wireless Power Consortium's wireless charging specification. Its defining change is mechanical: magnets in the transmitter and receiver hold the coils in a known relative position before charging begins. Because alignment no longer varies, coupling losses become predictable and higher power levels become practical. Everything else about Qi2 — the higher wattage, the thermal headroom, the accessory ecosystem — follows from that one change.
Start with the geometry, not the wattage
Wireless charging transfers energy across an air gap between two coils. How much of that energy arrives depends on how well the coils are coupled, and coupling depends on alignment. Move a phone a centimetre off centre and the coupling falls; the energy that does not transfer becomes heat, in the coils, in the shielding, in the phone's back panel.
For most of the history of wireless charging, alignment was the user's job. You put the phone down and hoped. The specification had to accommodate the worst case, which is why the original profiles have a comparatively low power ceiling: the system cannot know whether the coils are aligned, so it must stay within limits that are safe when they are not.
Qi2 changes that by making alignment mechanical. Magnets in the transmitter and the receiver pull the two into a fixed relative position before power transfer starts. The system now knows where the coils are.
That single change is the whole of Qi2. Everything else attributed to it — the higher power, the steadier charging rate, the thermal headroom — is a consequence.
What the specification family actually contains
Qi2 is not a replacement for Qi. It is the current generation of the same specification, and it carries the original inductive profile forward alongside the new magnetic one.
The baseline profile is the original arrangement: a device placed on a pad, aligned by hand. It carries the lowest power ceiling of the family because it must remain safe under worst-case alignment.
The magnetic power profile is the addition. Coils are held in a known position, so the system can push more power through the same air gap without exceeding thermal limits.
A product can be certified against either profile. A charger certified against the baseline profile is a Qi2 product; it simply is not a magnetically aligned one. This matters when reading a specification sheet, because "Qi2" alone does not tell you which profile is implemented, and a device supporting only one will not charge on a transmitter supporting only the other.
Revisions, and why the numbers keep moving
Qi2 is a specification family rather than a frozen document. The magnetic profile was introduced with the first Qi2 release in 2023. A later revision, published at the end of 2024 and widely referred to as Qi2.2, raised the maximum power of the magnetic profile and tightened the thermal requirements that accompany it.
Two practical points follow:
Certification does not carry forward automatically. A product certified against an earlier revision is not certified against a later one. Where a supplier claims the higher power level, the claim should be checkable in the consortium's certification database.
The charger is only half the system. A transmitter capable of the higher power level delivers it only to a receiver that also supports it. A phone that implements an earlier revision will charge at its own rate on a newer charger, and there is nothing wrong with either product when that happens.
The thermal consequence
Alignment improves efficiency, but it does not eliminate losses. Wireless charging remains a process in which a meaningful fraction of the energy never reaches the battery, and that fraction becomes heat in the space between the pad and the device.
Magnetic alignment makes that heat more predictable, which changes the design problem from "keep it safe under any alignment" to "manage a known thermal load". Predictable is easier to design against, and it is why the higher power levels became achievable at all.
It does not, however, make the heat disappear. A magnetic charger running at its maximum is still producing waste heat in a confined space, and a product that ignores this will derate early or run hotter than its housing was designed for.
What this means for a product team
Decide the profile before the industrial design. The magnetic profile imposes a fixed mechanical interface. Cases, mounts, stands, wallets and car holders all have to respect that geometry. Choosing the profile after the enclosure is drawn means redrawing the enclosure.
Test foreign object detection properly. FOD is the safety function that stops a transmitter when a conductive object — a coin, a key, a card with a metal layer — is inside the field. It is one of the few behaviours a buyer can test cheaply and meaningfully: put a coin under a phone on the pad and leave it. A competent implementation will not let the coin become hot.
Validate against the devices your customers actually own. Alignment is fixed by the magnets, but the receiver's coil, its shielding and its thermal path still vary by handset. Performance measured against one reference device is not performance.
Expect the accessories to be the hard part. The electrical design of a magnetic charger is well understood. The mechanical design — grip strength, release force, thickness, the behaviour of the magnet array next to a bank card — is where products in this category actually differentiate.
The claim worth checking
Wireless charging certification is issued by the Wireless Power Consortium under its own scheme. It is not issued by the manufacturer, and a logo on a product page is not evidence of anything.
The consortium maintains a certification database. If a supplier claims certification and the product is not in that database, the discrepancy is the finding. This is the single cheapest due diligence step available in this product category, and it takes about a minute.