How batteries work Chapter 18 Recycling

Chapter 18

End of life: recycling of lithium-ion batteries

What happens to a battery when it is finished?

Figure 18.1 The recycling routes for lithium-ion batteries: collection of spent cells as hazardous goods, pre-treatment, crushing and sorting, then pyrometallurgy giving a copper-nickel-cobalt alloy with lithium and manganese in the slag, hydrometallurgy giving metal salts, or direct recycling keeping electrode materials whole, all feeding back into new cells.
The recycling routes: three ways back into a new cell. Try this: follow the blue dot and, at each route, note what is recovered and what is lost.
SourceCollection, pre-treatment, pyrometallurgical, hydrometallurgical and direct recycling, with their recovered products, advantages and drawbacks, after Fichtner et al. 2022, section 6. The flow is schematic; real plants combine steps.

Even a cell that is used kindly reaches the end of its life. What becomes of it then? Recycling a lithium-ion battery means recovering above all its cobalt, lithium and nickel, besides aluminium and copper. Two chemical routes dominate: pyrometallurgy, which smelts the cells at about 1000 °C into a copper-nickel-cobalt alloy while lithium and manganese go to the slag, and hydrometallurgy, which dissolves the electrode materials in acid and separates the metals, with higher recovery and lower energy use but more complex processing. Direct recycling, which keeps the electrode materials whole, is still immature.1

Why does this matter? Cobalt is scarce, costly and toxic, which is one reason the positive electrode has moved from LiCoO2 toward materials with less of it.2,3 Lead-acid batteries show what a closed loop can look like: by a 2004 account, about 98 % of them were recycled in the United States.4

A loop can only close if the spent cells are collected in the first place. For lithium batteries, a 2020 European proposal would raise the collection target for portable batteries from 45 % to 65 % by 2025 and 70 % by 2030, and require all batteries from electric vehicles and stationary storage to be collected and recycled.1

Where does the lithium come from in the first place? It is extracted from brines and from minerals rich in it, spodumene, petalite and lepidolite, and spodumene is commonly processed with sulfuric acid. About 130 000 tonnes of lithium were mined in 2022, with about 15 tonnes of CO2 emitted per tonne of lithium. The International Energy Agency put lithium-ion battery waste from electric vehicles at about 500 000 tonnes, expected to rise to 8 million tonnes by 2040; about 97 000 tonnes of lithium-ion batteries were recycled worldwide in 2018. The European Union has made battery manufacturers responsible for collecting batteries at the end of their life.5

From my own work. The organic electrode materials of my doctorate were designed with their end of life in mind: I developed a route that recovers the organic precursor from a cycled electrode material, Mg(Li2)-p-DHT, and separates the streams containing lithium and magnesium (manuscript in preparation).

You can now explain what thermal runaway is and what breaks the loop, why lithium cells need electronics as well as chemistry to stay safe, why temperature and state of charge decide how a cell ages, and the three ways its materials can go back into a new cell.

This is where my own work starts: the research behind these pages.

The mathematics of this chapter

E = Q ⟨V⟩the energy a short circuit can turn into heat: all the charge stored times the average voltage (chapter 4); a 3 Ah cell at 3.7 V holds 11.1 Wh, that is 40 kJ

Q̇ = I(U − V) − I T dU/dTthe heat a cell makes in normal use (chapter 5, figure 5.5); in runaway the side reactions add their own heat on top

LSEI ∝ tbthe ageing law of chapter 16 behind the advice to avoid long periods at full charge

References for this chapter

Numbers in the text refer to this list. All references of the course, with the chapters that use each one.

  1. 1 M. Fichtner, K. Edström, E. Ayerbe, M. Berecibar, A. Bhowmik, I. E. Castelli, S. Clark, R. Dominko, M. Erakca, A. A. Franco, A. Grimaud, B. Horstmann, A. Latz, H. Lorrmann, M. Meeus, R. Narayan, F. Pammer, J. Ruhland, H. Stein, T. Vegge, M. Weil, "Rechargeable Batteries of the Future—The State of the Art from a BATTERY 2030+ Perspective", Advanced Energy Materials 12, 2022, 2102904. doi:10.1002/aenm.202102904
  2. 2 H. Zhang, C. Li, G. G. Eshetu, S. Laruelle, S. Grugeon, K. Zaghib, C. Julien, A. Mauger, D. Guyomard, T. Rojo, N. Gisbert-Trejo, S. Passerini, X. Huang, Z. Zhou, P. Johansson, M. Forsyth, "From Solid-Solution Electrodes and the Rocking-Chair Concept to Today's Batteries", Angewandte Chemie International Edition 59, 2020, 534-538. doi:10.1002/anie.201913923
  3. 3 D. Shanmukaraj, P. Ranque, H. Ben Youcef, T. Rojo, P. Poizot, S. Grugeon, S. Laruelle, D. Guyomard, "Review—Towards Efficient Energy Storage Materials: Lithium Intercalation/Organic Electrodes to Polymer Electrolytes—A Road Map (Tribute to Michel Armand)", Journal of The Electrochemical Society 167, 2020, 070530. doi:10.1149/1945-7111/ab787a
  4. 4 M. Winter, R. J. Brodd, "What Are Batteries, Fuel Cells, and Supercapacitors?", Chemical Reviews 104, 2004, 4245-4269. doi:10.1021/cr020730k
  5. 5 O. Faruque, M. J. Isalm, O. Faruq, M. M. Alam, "A comprehensive review of past and present developments of Li-ion batteries", Discover Sustainability 7, 2026, 881. doi:10.1007/s43621-026-02920-8
  6. 6 J. B. Goodenough, "How we made the Li-ion rechargeable battery", Nature Electronics 1, 2018, 204. doi:10.1038/s41928-018-0048-6
  7. 7 K. Brandt, "Historical development of secondary lithium batteries", Solid State Ionics 69, 1994, 173-183. doi:10.1016/0167-2738(94)90408-1
  8. 8 J. B. Goodenough, K.-S. Park, "The Li-Ion Rechargeable Battery: A Perspective", Journal of the American Chemical Society 135, 2013, 1167-1176. doi:10.1021/ja3091438
  9. 9 K. Abe, "Nonaqueous Electrolytes and Advances in Additives", in T. R. Jow, K. Xu, O. Borodin, M. Ue (eds.), Electrolytes for Lithium and Lithium-Ion Batteries, Modern Aspects of Electrochemistry 58, Springer, New York, 2014, 167-207. doi:10.1007/978-1-4939-0302-3_3
  10. 10 L. von Kolzenberg, A. Latz, B. Horstmann, "Solid-Electrolyte Interphase During Battery Cycling: Theory of Growth Regimes", ChemSusChem 13, 2020, 3901-3910. doi:10.1002/cssc.202000867
  11. 11 B. Horstmann, F. Single, A. Latz, "Review on multi-scale models of solid-electrolyte interphase formation", Current Opinion in Electrochemistry 13, 2019, 61-69. doi:10.1016/j.coelec.2018.10.013
  12. 12 S. A. Arote, "Fundamentals and perspectives of lithium-ion batteries", chapter 1 of Lithium-ion and Lithium–Sulfur Batteries: Fundamentals to Performance, IOP Publishing, 2022, pp. 1-1 to 1-26. doi:10.1088/978-0-7503-4881-2ch1

Cite this page

Using this page in teaching, a thesis or an article? Cite it as follows; the date is the last update of the course.

Shyma Sajeevan, A. (2026). End of life: recycling of lithium-ion batteries. How batteries work. https://asajeevan.github.io/batteries/recycling/

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