# Elastic Hairy Nanoparticle Separator Coating for Enhanced Interfacial Stability in Lithium–Metal Batteries

## TL;DR

This paper introduces a safer and more effective method to coat lithium-metal batteries with hairy nanoparticles to prevent dendrite formation and improve battery performance.

## Contribution

The novel approach uses spray-coated elastic hairy nanoparticles on the separator, eliminating extra handling of reactive lithium.

## Key findings

- Spray-coated HNPs on the separator reduced lithium handling time during assembly.
- The separator coating achieved ∼86% capacity retention after 500 cycles.
- Uniform HNP deposition improved contact between the protective layer and the anode.

## Abstract

Hairy nanoparticles
(HNPs) provide excellent protection against
dendrite formation when applied as an artificial solid electrolyte
interface (aSEI) in lithium-metal batteries. ASEIs can be applied
to the lithium anode in three different ways: by drop casting, electrospinning,
and dip coating. However, each of these application techniques require
a significant amount of handling time for the highly reactive lithium.
Safer conditions during cell assembly would greatly improve the commercial
applicability of lithium metal batteries. Hence, alternative processing
of the HNPs in the cells was explored. HNPs with high elasticity were
spray-coated on the anode side of the separator, resulting in no additional
lithium handling time other than during cell assembly. This improved
the common downfall of separator coatings with limited contact between
the protective layer and the anode. Due to the more uniform HNP deposition,
the separator coating showed a capacity retention of ∼86% after
500 cycles.