The development of efficient electrochemical energy storage device is crucial for future renewable energy management. Aqueous rechargeable batteries (ARBs) are considered to be one of the sustainable battery’s technologies due to its low cost, ease of manufacture, high safety and environmental friendliness. However, some tough issues such as the narrow electrochemical stability window of water, chemical instability of electrode materials, uncontrollable dendrite growth and poor cycling lifespan severely limited the development of high-energy aqueous batteries with stabilization and infallible safety. This article mainly summarized current and future challenges and the advanced science and technology to meet these challenges of various ARBs such as aqueous Li/Na/K/Mg/Ca/Al/-ion batteries, aqueous flow battery and photo-responsive battery. In addition, the potential direction and future prospect of the further development of these system batteries are discussed. Finally, given the various technologies and their associated technical challenges, we are motivated to develop the 2022 roadmap on aqueous batteries.

In the context of growing demand on energy storage, exploring the holistic sustainability of technologies is key to future-proofing our development. In this article, a cradle-to-gate life cycle assessment of aqueous electrolyte aluminum-ion (Al-ion) batteries has been performed. Due to their reported characteristics of high power (circa 300 W kg−1 active material) and low energy density (circa 15 Wh kg−1 active material), these results were compared with those of supercapacitors (per kW). Initial findings suggest these aluminum-ion cells have fewer environmental impacts than commercial supercapacitors, hence offering a more environmentally sensitive energy storage technology solution. Al-ion batteries are in their early development, and this result shows a strong argument for continuing research into this technology alongside other emerging energy storage systems.

The drive to decarbonise our economy needs to be built into our technology development, particularly in the energy storage industry. A method for creating performance targets for battery development based on environmental impact is presented and discussed. By taking the environmental impact assessments from existing lithium-ion battery technology—it is possible to derive energy density, cycle life and % active material targets required to achieve equal or better environmental impacts for emerging technologies to use. A parameter ‘goal space’ is presented using this technique for an aqueous aluminium-ion battery in its early development. This method is based on the main reason for battery technology advancement—the mitigation of climate change and the reduction of overall CO2 emissions in society. By starting out with targets based on emission data, sustainability will be at the centre of battery research, as it should be.

This systematic review covers the developments in aqueous aluminium energy storage technology from 2012, including primary and secondary battery applications and supercapacitors. Aluminium is an abundant material with a high theoretical volumetric energy density of –8.04 Ah cm−3. Combined with aqueous electrolytes, which have twice the ionic storage potential as non-aqueous versions, this technology has the potential to serve many energy storage needs. The charge transfer mechanisms are discussed in detail with respect to aqueous aluminium-ion secondary batteries, where most research has focused in recent years. TiO2 nanopowders have shown to be promising negative electrodes, with the potential for pseudocapacitive energy storage in aluminuim-ion cells. This review summarises the advances in Al-ion systems using aqueous electrolytes, focusing on electrochemical performance.