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It is no secret that a transition to alternative electrical energy generation must involve batteries unlike anything present in large scale energy storage or regulation. Rechargeable batteries must store the energy generated as well as complement those systems that depend on ever-changing inputs like wind or sun. These batteries must be tough enough to deal with the demands of us needy humans while having longevity and efficiencies that make it all worthwhile.
Yi Cui and a team from Stanford believe they have solved a chunk of the puzzle. They have devised a way to make batteries with electrodes that last far longer than current batteries and can deal with fast and frequent discharge cycles efficiently. The team achieved this by making the cathode and anode out of materials that allow for much easier conductance of electrons, and thus reduce electrode erosion or degradation, which is common with conventional batteries and leads to their breakdown.
The team made a cathode using copper hexacyanoferrate and embedded potassium ions into it. A hybrid anode, made out of carbon/polypyrrolea (a conductive polymer), plus aqueous electrolyte complete the fundamentals of this durable battery. The cathode suffers from little hysteresis after thousands of cycles of reaction and performs at a high-efficiency of 95% at a discharge cycle of 5C (5 discharges per hour or a discharge in 1/5th of an hour) and at 79% energy efficiency at the demanding rate of 50C. The team claims they detected zero-capacity loss after 1,000 deep-discharge cycles.
The materials they used to build this potassium ion battery were cheap and commercially available. Their durability and resilience makes them excellent for putting up with fluctuating energy generation of popular renewable systems, in other words, they can handle the high demand and help regulate the grid.
Until we find the solutions, we will keep shedding light on all these options. There is no denying, we are moving closer to sustainable living.
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