Alasmis develops alumina tech for battery separator

South Korean start-up Alamis has developed plate alumina that will be used to coat separators in lithium-ion batteries, the company said on Friday.

It is a first for a South Korean firm to develop the core material alumina used to coat separators. The market is currently dominated by Japan’s Sumitomo.

Separators in batteries prevents the anode and cathode from making contact. 

They are usually made of polyethylene (PE) and polypropylene (PP). Coating is crucial in allowing the lithium-ions to move between the anode and cathode for electricity and charging. Circular alumina has been conventionally used for coating.

Alamis’ plate alumina is smaller and structurally more sturdy compared to circular alumina, the company said.

On average, the plate is only 50 nanometers thick, the company said, compared to circular alumina’s 170 nanometers.

Using thinner alumina can make the separators thinner and increase energy density in batteries, the start-up said.

Alumina plates are also more sturdy, Alamis said, which will allow complete separation of the anode and cathode and make batteries safer. The company was preparing plates in various thickness and structure so that there is enough space for lithium-ion to pass through the separator.

The company was also researching ways to increase the purity of the alumina plates to over 98% from the current 97%.

It has recently developed coating materials that mixes alumina needles with alumina plates.

Start-up to build pilot line in 2021

Alamis CEO Kim Choong-soo said the company was preparing samples to give to battery cell and separator makers.

Separator coating material market was dominated by Sumitomo, which controls around 60% market share, with the rest of the shares owned by companies in China and Germany, Kim said. Alamis’ goods will allow South Korean companies to reduce reliance on imports from them.

Separator is a crucial material in battery that accounts for some 20% of cost in making batteries __ anode is the priciest at 40%. 

Alamis was founded in August, 2015. Its alumina plate development project was selected by the Accelerator Investment-Driven Tech Incubator Program for Startup, or TIPS, for support in November, 2018. Alamis is expected to complete development by November this year.

It received 500 million won in funding from Magna Investment in its Series A funding round. 

The company posted 500 million won in sales last year and is aiming for 1.5 billion won this year.

Alamis will construct a pilot line for the alumina next year. It is planning to have a production capacity of 40 metric tonnes per year by 2022 and 1,000 metric tonnes by 2025.