Apple has been granted a patent (number US 11658443 B2) for “liquid detection and corrosion mitigation.” The goal is to make its devices more spill-proof.
About the patent
In the patent Apple points out that power and data can be provided from one electronic device to another over cables that can include one or more wire conductors, fiber optic cables, or other conductors. However, the various contacts in connector inserts, in connector receptacles, or on a surface of a device, can be exposed to the local environment where they can encounter liquid, moisture, or other damaging contaminants.
For example, liquids can be spilled on these contacts or a device can be set down such that its contacts land in a puddle of liquid. Users can swim or exercise while wearing or holding an electric device. These activities can put contacts for the electronic devices in a position to encounter various contaminants such as chlorinated water, sweat, or other moisture.
These liquids, moisture, or other contaminants can corrode and damage the contacts. This corrosion can be greatly exacerbated by the presence of an electric potential, such as when a voltage is applied to a contact. Apple wants its devices to be able to detect the presence of moisture or other contaminant at a contact so that the possible damage can be mitigated.
Summary of the patent
Here’s Apple’s abstract of the patent: “Methods, structures, and apparatus that are able to detect the presence of liquid, moisture, or other contaminants in or on a connector. Examples provide a connector having a dedicated liquid-detect contact that does not have a corresponding contact in a corresponding connector. Examples provide liquid-detect circuitry that can use the liquid-detect contact to determine the presence of a liquid on or in the connector and can perform self-diagnostic tests such as continuity checks and calibration.”