Zero power bank lets users replace its batteries instead of replacing the device

Paris-based CTRL Energy has designed a 21,000mAh power bank with replaceable cells, swappable accessories and the ability to link into a larger power station.

CTRL Energy, a Paris-based company, is taking an overtly anti-disposable approach to portable charging with a device called Zero. Rather than treating a power bank as something to replace when its battery degrades, the design is meant to be opened, repaired and reconfigured over time. The product is built around a 3D-printed shell and a modular layout that allows users to swap components instead of discarding the whole unit.

At the core of the device are six replaceable 3,500mAh 18650 lithium-ion cells, giving Zero an overall capacity of about 21,000mAh. Access to the batteries is provided by a magnetic lid, which can be removed without tools. CTRL Energy says it recommends validated replacement cells from brands such as Samsung, LG and Molicel, underscoring that the unit is intended to be serviced by users rather than sealed shut as a throwaway accessory.

The power bank’s charging hardware is unusually ambitious for its class. It includes USB-C input and output rated at up to 100W, an 18W USB-A port and 15W wireless charging. That means the device is meant not only to recharge phones, tablets and laptops, but also to replenish itself at high speed when paired with a suitable power source. According to reporting by New Atlas and Electronics For You, the design also supports magnetic add-ons such as extra ports, a torch and a solar charger.

The modularity goes further than simple repairability. CTRL Energy says users can attach a snap-on light for filming or face-tracking tripods, while a separate accessory lets up to five Zero units link together into a larger power station with a combined 105,000mAh capacity. There is also a cut-out at the top that can function as a carry handle or lanyard point, plus support for a 3D-printed cable winder. These details suggest the company is trying to position the product as a small ecosystem rather than a single-use battery pack.

CTRL Energy has also introduced a smaller model called Subzero, which keeps the same modular idea but uses a replaceable 5,000mAh cell. Taken together, the two products reflect a wider push in consumer electronics towards repairable hardware, a response to growing concern over waste, battery replacement and planned obsolescence. In that sense, Zero is less a conventional power bank than a statement about how portable electronics could be built if longevity were treated as a design requirement rather than an afterthought.