UV-Sterilising Charging Base with Integrated Power Bank
A desk charging base that sterilises its own power bank — sliding enclosure, wireless charging pad and UV chamber packaged around a fixed battery footprint.
A charging base for a desk that does two things at once: charges a phone wirelessly on the outside, and sterilises a removable power bank inside.
The problem
Three subsystems wanted the same few centimetres:
- The power bank had a fixed footprint — the client wanted it dimensionally matched to a standard 4.13 × 2.62 × 0.45 in battery pack, so it was an input, not a variable.
- UV sterilisation only works on surfaces the light reaches. A chamber that merely encloses the battery does nothing for the faces in shadow.
- Wireless charging has a distance budget. Inductive coupling fails if the coil sits too far from the phone, which put a hard ceiling on how much structure could go above the coil.
Then the client’s team asked for the outer pad to be roughly half the size and, ideally, retractable from under the box.
The approach
- Coil clearance treated as a constraint, not a preference. The battery bay could not be raised, because raising it meant losing wireless charging — that trade-off was surfaced early rather than discovered in testing.
- A sliding door instead of a lid, so the enclosure opens without needing headroom above the unit on a crowded desk.
- Chamber geometry driven by line of sight, with the battery held away from the walls so UV reaches the faces that matter.
- Retractable pad evaluated honestly. A pad that pulls out from under the body was assessed against complexity and cost, so the client could choose with the mechanism understood rather than assumed.
The result
A complete design for the base, the sterilising chamber and the matched power bank, developed across several revisions as the client’s team refined the product’s proportions.
Where this applies
Consumer electronics where a fixed component — a battery, a board, a coil — sets the rules and the product has to be designed around it. The engineering value is in knowing which constraint cannot move.
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