Low-Temperature and Acid-Free Platform Technology for Direct Regeneration and Circular Recycling of Lithium-Ion Battery Materials

ReCell K1’s proprietary low-temperature (<400°C) acid-free direct recycling platform (TRL 6-7, pilot-validated) for spent lithium-ion batteries employs pyrolysis under oxygen-deficient conditions to recover high-purity Li₂CO₃, Ni/Co/Mn metals from NCM cathodes, and graphite, while preserving the LFP cathode’s crystalline structure for direct regeneration, eliminating strong acids, achieving >98% metal recovery, and reducing energy use by 40–70% vs. conventional methods.

ReCell K1’s Low-Temperature and Acid-Free Platform Technology is a direct recycling and regeneration system for spent lithium-ion batteries, operating below 400°C without strong acids. It replaces conventional high-temperature smelting (≥1,200°C) or sulfuric-acid leaching with a three-stage process: pre-treatment (pyrolysis), post-treatment (recovery), and optional regeneration. The technology achieves ≥98% metal recovery, reduces energy use by 40–70%, and eliminates wastewater and sludge, aligning with EU circular economy and decarbonization goals.

Stage 1: Pre-treatment (Low-Temperature Pyrolysis)

Intact, fully discharged battery cells enter the system without mechanical crushing or shredding. A proprietary pyrolysis process (≤400°C) in an oxygen-deficient atmosphere decomposes organic components (binder, separator, electrolyte), producing a Black Metal Mass (BMM) or Black Metal Powder (BMP) with reduced metal compounds and Li₂CO₃.

NCM Batteries (Li[NiₓCoᵧMn_z]O₂):
- Layered cathode structure decomposes; nickel and cobalt ions are reduced to Ni-Co alloy, while manganese ions form MnO compounds.
- Lithium reacts with carbon species from organics, forming Li₂CO₃ during pyrolysis.
- Ni-Co alloy enables magnetic separation from other materials.

LFP Batteries (LiFePO₄):
- Olivine cathode structure is preserved after full discharge, allowing lithium ions to migrate back into the LFP lattice.
- Pyrolysis removes organics while maintaining the crystalline integrity of LiFePO₄.
- CNT coating on LiFePO₄ particles remains intact.
- Current collectors (Cu/Al) are automatically separated during processing.

Stage 2: Post-treatment (Recovery)

The BMP undergoes water-based separation without strong acids:

- Li₂CO₃ is selectively dissolved in water and recovered via vacuum evaporation; water is recycled through condensation columns.
- NCM Pathway: Ni-Co alloy and MnO particles are separated via magnetic and physical methods.
- LFP Pathway: LiFePO₄ particles and graphite are separated from current collector fragments.

Stage 3: Regeneration (Optional)

Recovered metal powder is converted into an aqueous sulfate solution using magnetically enhanced bioleaching:

- Acidithiobacillus ferrooxidans bacteria produce biogenic H₂SO₄.
- An external magnetic field (>5 mT) enhances dissolution: 85% Ni, 95% Co, 100% Mn after 3 days (vs. 20–40% without the field).
- The resulting sulfate solution serves as a cathode precursor for direct reuse in battery manufacturing, enabling a closed-loop circular economy.

Basic information about the technique

Production data

Associated main production process(es) and product(s): NCM and LFP battery recycling

Production data: 30 tonnes/day

Participant Companies