Soon, replacing your iPhone’s existing battery won’t be a dicey exercise of poisonous chemicals, delicate microchips, glue-peppered hand soap and a prayer. Citing leaked plans, the business site The Information reported last week that Apple is looking to equip future iterations of the iPhone with modular batteries that customers could more easily replace.
And there it is, from the horse’s mouth: ‘The new technology – electrically induced adhesive debonding – involves encasing the battery in metal, rather than foil as it is today. That way you could then pry the battery out of the chassis with a little jolt of electricity to the battery that the people say they will be able to do.’
Apple is changing their mind because, after years of complaints from repair professionals and DIYers, they’ve seen fit to finally get rid of that pesky glue. iFixit had to write at length in an article called ‘Why Electronics Rely on Glue—and Why They Shouldn’t’, after all.
On an iPhone from 2020, that can be up to two hours of disassembly, an hour to clean up the destruction from water damage and then another hour of glue to put it back together,’ the article said.
Why Apple is doing this
Why now? The reason is the E.U. and its march towards a greener, more sustainable future. Last year, the European Commission introduced the Batteries Regulation, which, besides other things, wants to deal with the situation in a more satisfactory and less wasteful way. Here are the main points:
Recycling efficiency, material recovery and recycled content targets will be progressive and introduced from 2025 onwards, with all collected waste batteries to be recycled, and high recovery targets set.
As from the year 2027, the portable batteries inside target electronic products can be detached or replaced at any life cycle phases.
Any portable batteries fitted into an appliance shall be removable and replaceable by the end-user or by independent operators during the lifetime of the appliance, if the battery has a shorter lifetime than the appliance, or at the latest at the end of the lifetime of the appliance.
‘Thanks to this victory for the right to repair, any new portable devices and light modes of transport on the market will have to be designed to incorporate replaceable batteries,’ said Cristina Ganapini, coordinator of the Right to Repair (Europe). The full proposal is available here (PDF).
A bit of ionic magic
In short, how does Apple’s transition to the mystery of ‘electrically induced adhesive debonding’ actually work? Strong adhesive bonds that easily, instantly and energetically allow for electricity-aided separation, that’s the promise. Researchers describe it like this in a paper published in February in the journal Materials Today Communications: ‘It is strongly desired for urgent cases or components with frequent disassembly.’
These industries will have a keen interest in electrical removability, so their circuitry can still have fragile electronic components that must be attached using electrically removable adhesives. Imagine how much simpler it would be to get a power adapter working if you could just attach and detach the components with a zap of electricity, using conductive adhesives to attach the components to the circuit board.
Less of removing and replacing faulty elements.
Another benefit of these adhesives is that they can be actuated remotely, obviating the need for physical contact with the joined elements. ‘Smartphone assembly today still relies on high-temperature melting to apply or remove glues, and the method we’ve described does the same, yet uses electrical stimulus rather than heat.
Switching to the electric option nevertheless sidesteps most of them. It requires adding ionic components: salts that are able to dissolve in the glue or can replace the adhesive altogether with an ionic liquid. Since these additives provide the glue with ion-based conductivity, it now obeys an electrical stimulation.
Voltage-activated debonding would also mitigate the need for mechanical, thermal or chemical damage to the internal components of a phone. Except for the array of conductive patches, the whole concept necessitates the use of a conductive substrate such as metals or any materials that can be shellaced with a conductive layer.
When they are there, debonding can be triggered by providing a voltage across the two surfaces. Thanks to its intriguing applications and added value over current bonding techniques, the technology is attracting impressive interest in the aerospace and electronics segments, with iPhones set to be the first large-scale adopters of the technology in the near future.
For the science behind the electrical adhesion and debonding at the microscopic level, look at the paper published in the journal Advanced Materials Interfaces, and this great thesis submitted to the School of Chemical Science and Engineering, Kungliga Tekniska Högskolan, in Sweden. For the full technique, here, in the context of recycling, at the Royal Society of Chemistry.