A new approach to alkali batteries, in which the cathode is dissolved in water that flows through the system, could overcome the limitations of currently available batteries, scientists in the US say. Rechargeable lithium-ion batteries have revolutionised the mobility of small electronics, but their limited capacity means they don't stretch easily to bigger jobs such as running automobiles or storing power for national grid networks.Ordinarily, lithium ion batteries contain a solid anode, which gives up electrons, and a solid cathode, which receives them. The two are divided by an organic fluid electrolyte. This strategy depends on a cathode that can expand to...