Recycling

Introduction

Worldwide, the enthusiastic adoption of lithium-ion batteries (‘LIBs’), particularly as a source of portable power, is creating environmental concern, given that only around 9% of spent batteries are recycled to keep them out of landfill and recover valuable metals. (In Australia, the recycling rate is woeful: less than 3%.) In fact, the large quantity of batteries discarded globally actually represents a potentially significant resource.

At present Belgium, South Korea, China and Canada recycle the most batteries, with the metals they contain generally recovered by smelting. Pyrometallurgical processes, however, are highly disadvantageous for recovering lithium, since the element’s extreme volatility means it is usually lost in flux or off-gas. The flux is generally not reprocessed, being used instead as aggregates and fillers, which precludes reuse of the lithium. Research into recovering lithium through the condensation of smelter off-gas, however, is currently underway.

Processing techniques

Pyrometallurgical processing of spent LIBs can efficiently recover nickel, copper, cobalt and manganese from LIBs but not the lithium. Nor does pyrometallurgical processing recover graphite from LIBs. Moreover, volatilisation of the complex polymers in LIB binders and separators presents an atmospheric emission risk.

A potential alternative to the downsides associated with pyrometallurgical processing is therefore a hydrometallurgical approach.

Lithium Australia is developing a hydrometallurgical technique that recovers all metals, including lithium, from spent LIBs. The R&D involved is being undertaken in conjunction with Murdoch University, with a final flowsheet to be pilot-tested in the near future.

Collection logistics

While it may seem that the key to efficient LIB recycling is product preparation prior to hydrometallurgical recovery, in fact that is not the case. The greatest challenge remains logistics – collecting enough batteries to support a viable enterprise. An inability to aggregate the feed for recycling plants is the main reason that recycling rates remain so low.

Partnering with Envirostream Australia

Given the CSIRO’s April 2019 forecast that the amount of discarded LIBs in Australia will grow from the 3,300 tonnes recorded in 2016 to between 100,000 and 188,000 tonnes by 2036, Lithium Australia believes more efficient recycling of battery waste is imperative. Therefore, Lithium Australia is investing in the logistical infrastructure necessary to recycle LIBs through a partnership with Envirostream Australia, which supports recycling nationwide and will apply its collection know-how to other jurisdictions in due course.