As a result of a European Union push to improve repairability of consumer devices like smartphones, Apple believes it should make iPhone batteries user-replaceable by 2027. ReportedlyThis led Apple to consider using electrical adhesives rather than traditional glues, which require heat, isopropyl alcohol, violence, or all of the above to remove. Details are scarce, but the general idea seems to be that encasing the battery in metal, combined with the inside of the metal casing, creates a cation/anion pair that can be permanently bonded by passing a low-voltage DC current through it.
This is not a completely outlandish idea: tesa has already commercialized it with the electro-peel method. On-demand peeling productThis involves the application of a tape applied to one side of the (metal) surface and applying a pressure of 5 bar for 5 seconds, after which the two parts can be removed again without residue, as shown in the image above. This involves the application of a 12V DC voltage for 60 seconds, after which the two parts can be removed without force.
tesa sells it alongside the pull tab adhesive strips that are all the rage on smartphones at the moment, but opinions on pull tabs for battery changes are very divided. It’s always good to keep a bottle of IPA on hand for those times when the pull tab inevitably comes off and you have to pry the battery out. On that note, peel-off electro-adhesive would make life a lot easier, as the days when batteries were not a structural part of smartphones are unlikely to come back, no matter how much we miss them.
We’ve covered electrochemical adhesion before, a technique that can bond everything to anything, from biological tissue to graphite to metals, which has exciting applications in robotics and medicine.