Technology & process
Prelithiation, developed against your material system
Prelithiation describes the controlled introduction of lithium into an electrode or cell component before normal cell operation begins. It is considered where lithium consumed in the first cycles limits usable energy density, or where new material combinations have to be validated.
Why it is considered
During the first charge and discharge steps, part of the available lithium is consumed and is no longer available for reversible cycling. Prelithiation is one of the approaches evaluated to address this, and it can also be used to investigate how materials, binders and electrolytes behave together under defined conditions.
Material-neutral scope
The technology scope is relevant to battery-cell chemistries that use lithium ions for energy transport or storage — including graphite, silicon, composite anodes and other advanced active materials. Universal compatibility is not implied: suitability depends on the material system, cell chemistry, performance target and process conditions.
Seven approaches
Prelithiation methods and how they are compared
We work across all seven approaches. Comparison and selection are part of the development work — no method is presented as always best.
| Method | Principle | Typically considered for | Points to evaluate |
|---|---|---|---|
| Electromechanical prelithiation (HypSi™) | Lithium is introduced and the SEI is pre-formed in one continuous step, combining electrochemical transfer with mechanical contact under controlled conditions. | Development and production where dosage control, speed and roll-to-roll integration are needed together. | Requires electrode-specific dose design; process conditions are defined per material system together with 70.energy. |
| Electrochemical prelithiation | Lithium is introduced by electrochemical transfer in a dedicated treatment step. | Development work where lithium dosage has to be adjusted precisely and reproducibly. | Requires a dedicated treatment setup and electrolyte compatibility. |
| Chemical prelithiation | Lithium is introduced via a chemical reaction with a lithium-containing reagent system. | Material screening and cases where an electrical process step is not preferred. | Reagent handling, reaction control and material compatibility have to be evaluated per system. |
| Direct-contact prelithiation | The electrode is brought into contact with a lithium source under defined conditions. | Electrode-level trials and comparative studies on prepared electrode sheets. | Contact conditions, atmosphere control and homogeneity require careful process definition. |
| Cathode additives | A lithium-donating additive is included in the cathode formulation and releases lithium during formation. | Approaches that integrate additional lithium into an existing cathode-coating workflow. | Gas release, occupied cathode volume and the long-term inertness of additive residues must be evaluated. |
| Stabilised lithium metal powder (SLMP) | Lithium metal micro-particles with a protective shell are applied to the anode. After electrolyte filling, the shell dissolves and lithium transfers into the anode. | Approaches close to existing electrode coating lines. | Powder handling and safety, distribution uniformity, and lithiation occurring only inside the cell. |
| Vapour-phase prelithiation (PVD) | A thin lithium film is deposited onto the anode by physical vapour deposition in vacuum. | Very uniform, precisely dosed films for research and pilot work. | Costly vacuum equipment and immediate inert handling after deposition. |
Prelithiation routes at a glance
| Criterion | HypSi™ | Electrochemical | Chemical | Direct contact | SLMP | Vapour-phase (PVD) | Cathode additives |
|---|---|---|---|---|---|---|---|
| Dose control | High | High | Medium | Low–medium | Medium | High | Medium |
| Process time | From 70 s | Hours | Minutes–hours | Minutes–hours | In-cell, after filling | Minutes–hours (vacuum) | During formation |
| Roll-to-roll integration | Designed for it | Difficult | Possible | Possible | Possible | Possible, costly | Not needed |
| SEI pre-formed before cell assembly | Yes | Partly | Partly | Partly | No | No | No |
| Extra cell assembly/disassembly | No | Yes | No | No | No | No | No |
| Scale-up path | Lab sheet → coil | Limited | Moderate | Moderate | Moderate | Limited (vacuum cost) | Easy |
Each route has its place. HypSi™ was developed to combine the dose control of electrochemical prelithiation with the speed and line integration that industrial production requires.
The correct approach depends on the material system, development stage, equipment environment, target performance and economic requirements. We recommend discussing your specific system so the comparison can be made against your own constraints.
Development workflow
Seven steps, in sequence
The workflow is designed to make experiments repeatable and comparable rather than to produce isolated single results.
- 01
Define target performance
Clarify the electrochemical and commercial targets that the development work should support.
- 02
Analyse materials and cell chemistry
Review active materials, binder and electrolyte system, electrode design and cell format.
- 03
Compare and select a prelithiation method
Weigh the available approaches against the material system, development stage and equipment environment.
- 04
Calculate preliminary lithium dosage
Derive a first dosage estimate to be verified experimentally.
- 05
Develop the material-specific process
Develop and validate the approach for the selected material system with 70.energy.
- 06
Configure suitable laboratory equipment
Match electrode formats, throughput and monitoring needs to an equipment configuration.
- 07
Validate electrochemical results
Assess repeatability and comparability of results and refine the development approach.
Capabilities
Process advantages
These are capabilities that support investigation and optimisation. They are not guaranteed outcomes.
- Precisely adjustable lithium dosage
- Adaptable material-specific process development
- Repeatable and comparable experiments
- Compatibility evaluation for different anode materials
- Binder and electrolyte optimisation
- Integration into existing development workflows
Adaptable
Project scope
Parameters that can be adapted per project and documented for comparability.
- Electrode dimensions and formats
- Material-system compatibility
- Lab-to-line integration
- Anode material and composition
- Binder and electrolyte system
- Cell-design objectives
- Data collection and process monitoring
Objectives
Development objectives
Qualified objectives for development work. No fixed percentages are attached to them.
- Increase usable energy density
- Minimise initial capacity loss
- Improve cycle life and electrochemical stability
- Optimise active materials, binders, electrolytes, lithium dosage and material-specific process development
- Reduce technical decision time
- Establish a structured laboratory-development pathway
Binder and electrolyte optimisation
The binder holds the electrode structure together and the electrolyte governs ion transport and interface formation. Both interact strongly with the active material, so combinations are tested in a structured sequence rather than component by component. This work can be included in prelithiation-process development.
Coming soon
Lithium-dosage calculator for electrochemical prelithiation
A calculation tool for electrochemical prelithiation is under development and is not yet available on this site. Until then, a preliminary calculation can be discussed manually — describe your material system in the project form.
Related terms
Glossary
Short, qualified definitions of the terms used on this page.
In-depth articles on graphite prelithiation, silicon first-cycle loss, method comparison, lithium dosage and coulombic efficiency are collected in the prelithiation guides.
Discuss your project with a specialist
Share your material system and target performance. The first step is a free introductory expert call.