Page 104 - A Comprehensive Guide to Solar Energy Systems

Chapter 5 • Sustainable Solar Energy Collection and Storage 99

5.8 Resource-Efficiency and Circular Economy

5.8.1 Critical Materials

Critical materials used in batteries are shown in Table 5.4, along with their current
supply risk index from the British Geological Survey. The high supply risk associated
with vanadium may present future resource security issues for VrFBs, further justifying
its elimination as a suitable technology for this application. li-ion batteries face resource
security issues due to li, Co, graphite, and rare earths in the case of lithium-iron-yttrium-
phosphate batteries (lFyP), as do Aquion cells which contain graphite. In the interests
of global resource security, it is questionable whether technologies containing critical
materials should be utilized without further consideration of available infrastructure to
support closed-loop recycling, refurbishment and remanufacturing. lead-acid batteries
contain no critical materials.

5.8.2 End-of-life Prospects and Compatibility With Circular Economy

Closed-loop recycling of lead-acid batteries is well established in South Africa. First
National Battery operates a network of collection points across South Africa which divert
lead-acid batteries to their smelting facility in Benoni for recycling. recovered Pb and
plastics are used to manufacture new batteries with optimized design for disassembly
[43]. This suggests end-of-life costs will be low in comparison to other batteries which
cannot be recycled domestically, and that lead-acid batteries are an appropriate choice
for circular economy in South Africa, with environmental, economic, and social ben-
efits afforded through closed-loop retention of the materials within the South African
Economy. Materials cost savings resulting from use of recovered components/materials

Table 5.4 Supply Risks of Materials in Batteries, Critical Materials are Those
Highlighted in Bold
Element Relative Supply Risk Index [42] Relevant Battery Technology
REEs 9.5 LIBs (LFYP)
V 8.6 VRFB
Co 8.1 LIBs (NMC and NCA)
Li 7.6 All LIBs
Graphite 7.4 LIBs (LFP, LMO, NMC, and
NCA),Aquion
Mn 5.7 LIBs (LMO NMC), Aquion
Ni 5.7 LIBs (NMC and NCA)
Pb 5.5 VRLA
Fe 5.2 LIBs
Ti 4.8 LIBs (LTO)
Al 4.8 LIB
The supply risk index runs from 1 (very low risk) to 10 (very high risk); LFYP, Lithium-iron-yttrium-phosphate; LIBs, Li-ion batteries;
REEs, rare earth elements; highlighted elements are included in the EU20 critical list.