Ultrafast high-capacity NiZn battery with NiAlCo-layered double hydroxide

High-performance, low-cost, safe and environmentally friendly batteries are important for portable electronics and electric vehicles. Here, we synthesized NiAlCo-layered double hydroxide (LDH) nanoplates attached to few-walled carbon nanotubes (NiAlCo LDH/CNT) as the cathode material of a rechargeable NiZn battery in aqueous alkaline electrolytes. The alpha-phase nickel hydroxide with ultrathin morphology and strong coupling to nanotubes afforded a cathode with a high capacity of similar to 354 mA h g(-1) and similar to 278 mA h g(-1) at current densities of 6.7 A g(-1) and 66.7 A g(-1), respectively. Al and Co co-doping is unique for stabilizing alpha-phase nickel hydroxide with only a small capacity loss of similar to 6% over 2000 charge and discharge cycles at 66.7 A g(-1). Rechargeable ultrafast NiZn batteries with NiAlCo LDH/CNT cathode and a zinc anode can deliver a cell voltage of similar to 1.75 V, energy density of similar to 274 W h kg(-1) and power density of similar to 16 kW kg(-1) (based on active materials) with a charging time of <1 minute. The results open the possibility of ultrafast and safe batteries with high energy density.