New zinc batteries offer 10x more life, safer than lithium energy devices

Researchers have overcome critical challenges in developing fire-risk-free aqueous zinc batteries, which are secondary batteries that use water as the electrolyte. Their groundbreaking electrode manufacturing technology effectively controls dendrite formation in aqueous zinc batteries.

Developed by researchers at the Korea Institute of Energy Research (KIER), the new method makes zinc batteries environmentally friendly compared to lithium-ion batteries, which use volatile liquid electrolytes.

Additionally, since aqueous zinc batteries use two electrons per ion, they can theoretically offer more than twice the capacity of lithium-ion batteries, which use only one electron per ion, according to researchers.

A solution to the challenge of dendrite formation in metal batteries

“The significance of this research is that it provides a solution to the challenge of dendrite formation in metal batteries such as aqueous zinc batteries using low-cost processes and materials like copper oxide,” stated Dr. Jung-Je Woo.

“We aim to contribute to the commercialization of aqueous batteries through follow-up research that standardizes, and systematizes the developed electrodes.”

The batteries using the research team’s technology demonstrated a lifespan exceeding ten times that of conventional aqueous zinc batteries, increasing the potential for commercialization.

Battery maintains 80% of its capacity even after 3,000 cycles

In conventional aqueous zinc batteries, the formation of dendrites causes the capacity to decrease to below 80% after 300 charge-discharge cycles.

Researchers suppressed the dendrite formation and found that the battery maintains 80% of its capacity even after 3,000 charge-discharge cycles.

The research team successfully controlled zinc deposition to achieve a world-leading capacity of 60 mAh/cm². They also demonstrated the technology’s durability through extensive battery performance tests exceeding 3,000 cycles and confirmed its applicability to large-area electrodes measuring 64 cm².

Earlier, the primary method used to suppress dendrite formation involved adding promoters like copper to accelerate the initial growth of zinc and guide uniform deposition. However, a problem with this approach was that dendrite formation would recur with repeated charging and discharging cycles of the battery.

Unique electrode demonstrates exceptional stability

In response, the research team devised a method to control dendrite formation step-by-step using copper oxide. Like regular copper, copper oxide promotes the initial growth of zinc and guides its deposition. Additionally, copper oxide has optimized conductivity for depositing zinc in a uniform distribution, allowing for more efficient deposition compared to regular copper.

Researchers used copper oxide to promote uniform zinc deposition and control dendrite formation. When electrodes made using this method were applied to batteries, they demonstrated a lifespan more than ten times longer than conventional batteries, according to the study.

Published in Advanced Energy Materials , the study found that the unique electrode demonstrates exceptional stability, effectively controlling dendrite-free growth for thicknesses of up to 120 µm even in open-plating environments with an impressive areal capacity of 60 mAh cm−2.