In today's tech-savvy world, having a reliable source of portable power is essential, and a hefty portable power bank can be a game-changer for many. However, constructing one requires an assortment of compatible lithium-ion cells, which can be challenging to obtain. Enter Chris Doel, an innovative DIY enthusiast who has devised a clever solution to this issue. He advocates for repurposing lithium-ion cells salvaged from disposable vapes to assemble a robust 35-cell power bank. His mantra? Say no to single-use devices!

Chris has made it his mission to create practical gadgets, like power banks, using cells extracted from disposable vapes. On his quest, he has discovered an abundance of these vapes littered across urban landscapes, particularly after events such as music festivals. Notably, vape shops have proven to be valuable allies in his endeavor, often willing to part with their used devices when asked. The most labor-intensive part of this process is safely extracting the usable cells, a task Chris has mastered and refined into a meticulous art.

Interestingly, numerous vape models utilize similar cell types internally, which simplifies the salvage process. Once Chris has gathered 35 identical cells in good condition, he employs a compatible 3D-printed enclosure along with two printed circuit boards (PCBs) to connect the cells. A pre-constructed board is responsible for managing the power bank's functionality, including the recharging process.

Several design features of Chris's power bank stand out as particularly innovative. For instance, the power bank includes three flexible wings that cradle each cell. This design not only centers the cells but also holds them securely, accommodating slight size variations. Additionally, Chris utilizes spring terminals, eliminating the need to solder connections directly to each individual cell, which can be cumbersome and risky. The PCBs also serve an important dual purpose as cell balancers, ensuring that all 35 cells maintain an equal voltage level during the initial construction phase. Once the cells are confirmed to be balanced, a solder jumper located near each terminal can be closed to bypass this balancing feature for the final assembly.

The end result is a substantial power bank capable of powering a wide array of devices. Perhaps the most appealing aspect of Chris's innovation is its modularity; the power bank can be opened, allowing users to replace individual cells when they eventually reach the end of their lifespan. In the UK alone, an estimated 260 million disposable vapes are thrown away each year, each containing a rechargeable lithium-ion cell. This staggering statistic highlights the potential for creative hackers willing to invest some effort into repurposing these discarded devices.

If power banks are not quite your area of interest, Chris has also ventured into constructing a DIY e-bike battery utilizing salvaged cells, which can be a significant money-saving alternative for those looking to power their electric bikes.

For those intrigued by the intricacies of lithium-ion batteries and the technology behind them, Chris has shared a detailed video documenting his process, which is embedded below. Additionally, for a deeper understanding of lithium-ion batteries and their functionality, be sure to check out an informative piece by our own Arya Voronova.