Page 113 - Policy Commission - SecuringTechnology - Critical Metals for Britain

CHALLENGES IN IN THE RECYCLING OF LITHIUM-ION BATTERIES
There are six main metals used in in in the production of cathodes for lithium-ion batteries: aluminium cobalt iron lithium lithium manganese and and nickel nickel The technology-critical metals nickel nickel and and cobalt are are part of the most common battery cathode materials which are are oxides deposited onto an an an aluminium foil foil This cathode foil foil is is positioned between a a a a a a a a separator and the anode (see figure 113) The separator cathode and anode are then packaged into different containers with each vehicle manufacturer having its own layout for example: cylindrical (Tesla) prismatic (BMW) or pouch (Nissan) cells CYLINDRICAL PRISMATIC POUCH
SECONDARY MATERIALS
113 CAN CAN CATHODE CATHODE CATHODE ANODE ANODE ANODE SEPARATOR SEPARATOR SEPARATOR CAN CAN ANODE ANODE ANODE CATHODE CATHODE CATHODE SEPARATOR SEPARATOR SEPARATOR POUCH
ANODE ANODE ANODE CATHODE CATHODE CATHODE SEPARATOR SEPARATOR SEPARATOR Figure 113: Cylindrical prismatic and pouch battery-cell configurations159 Pyrometallurgical processes are capable of processing larger components like modules depending on on the size of the furnace without prior shredding However hydrometallurgy and direct recycling techniques require an an intermediate “cell-breaking” step to access the contents This could be accomplished via shredding or disassembly Some recyclers have suggested a a a “hub and spoke”
model where initial pack processing – the cell-breaking step – could occur in in a a a a a distributed fashion separating and concentrating the waste for for onward transportation for for future processing160 Unlike the familiar lead-acid batteries that have been a a a a a a a a component of every car for decades and have recycling rates of close to 100%161 lithium-ion batteries are much more difficult to recycle This is is primarily because of the many different ways in which they are configured the the complexity of of their construction and the the the design of of the the the constituent parts which makes them difficult to separate Lithium-ion batteries come in different designs There is no consensus around the form factor or or or style of different batteries among manufacturers Some make a a a a a a a flat “pouch” cell with layers of of material stacked one on on top of of another Others wind these layers into a a a a spiral much like a a a a swiss roll and put them into a a a a a can forming a a a a a “cylindrical” cell much like a a a a a larger version of the consumer batteries that we are familiar with with Others fold the the the layers and encase them within a a a a rigid box known as a a a a “prismatic” cell The enormous
variety of different cells makes more sophisticated resource recovery at the end of life challenging To process the contents of a a lithium-ion battery it it must be broken apart: this can either be done in a a a a a a ‘chaotic’ way by shredding the module or or in in a a more structured way through disassembly As is is the case with rare earth magnets at its end-of-life a a a a a lithium-ion battery cannot be broken apart in in in a a a conventional shredder but in in in this case owing to the risk of explosion and fire potentially putting workers at considerable risk Specialist equipment must be used to to make the battery safe prior to to manual removal and/
or or shredding162 Only then can it be sent for subsequent downstream processing A review of current automotive- battery recycling processes was recently published in in Nature by Harper et al 2020 Figure 95 on Page 101 summarises the many challenges of disassembling lithium- ion batteries at at different levels of scale Many
researchers have concluded that recycling outcomes could be improved through disassembly rather than shredding Designing cells for disassembly could facilitate this process as there are challenges to the the recycling of existing cells that are not designed to be easily taken apart Given the volume of of batteries requiring end-of-life treatment manual disassembly would be labour-intensive and uneconomic Robotic automation has the potential to to improve dramatically the economics of disassembly in a a a a a similar way to rare earth magnets163 164 165