Advances in energy storage devices in the next 10-15 years are expected to come from lithium-ion batteries¹. However, the current architecture used in Li-ion electrodes appears to pose a limit on energy and power densities in electrodes. New architectures are needed to design Li-ion batteries with the improved performance desired in advanced high-power applications.

Novel 3D Li-S battery architecture combines power density and energy density in a single battery in a way that a high surface area cathode and anode are interdigitated. Interdigitation allows multi-directional flow of Li ions compared to the one-directional movement in conventional 2D Li-ion batteries making the path length for Li ions short at all points between the electrodes.

The battery is fabricated using anode tin-nickel alloy (Ni₃Sn₄) deposited on high surface area nickel foam used as the negative electrode current collector. The anode is then conformally coated with a solid polymer electrolyte using layer-by-layer method. Remaining void spaces in the foam are filled with lithium sulfide (Li₂S) cathode using a slurry coating process. To complete the cell, nickel mesh current collector is applied to the slurry.

References

1. V. Sapru, September 2012. Frost & Sullivan Battery Power Conference, Slide 5.

Acknowledgments

The work has been supported by the targeted program No. 0115РК03029 “NU-Berkeley strategic initiative in warm-dense matter, advanced materials, and energy sources for 2014-2018” from the Ministry of Education and Science of the Republic of Kazakhstan.