Lithium Battery Chemistry — Part 2

Cathode active materials such as phosphates are typically produced via solid-state synthesis, requiring fine, well-mixed precursors and specific chemistries, or via hydrothermal and solution-based routes. These processes are often slow, cumbersome, and costly. LFP/LMFP benefits from a low congruent melting point, forming a homogeneous molten medium that favors fast, thermodynamically controlled, reversible synthesis. We have developed and patented a novel melt-synthesis process exploiting this behavior. This approach is highly versatile regarding precursor chemistry, purity, and morphology, enabling LFP/LMFP synthesis within minutes, reducing environmental impact and simplifying recycling of off-specification and spent-battery materials.

LMR materials historically exhibit persistent voltage fade, and require tailored electrolytes. Stratus Materials has developed an efficient and low-cost processing route that creates crystallographically stable cobalt-free LMR, called LXMO. Data will be disclosed showing that LXMO-based large-format cells (20Ah and larger) can exhibit energies of over 700 Wh/l, and cycle-life stability of over 2000 cycles. Lower energy density versions can compete economically with LFP cells in stationary use cases.

This talk presents the charge-discharge cycling performance of ZnNi rechargeable batteries using a new technology to suppress non-uniform reaction distribution of the anode which is the main reason of zinc dendrite generation and growth. The technology provides an excellent rechargeability for thousands of cycles without internal short circuit and capacity loss.

Despite significant promise, widespread adoption of sulfide solid-state electrolytes (SSEs) is hindered by processability in manufacturing environments and lifetime/performance limitations due to (electro)chemical instability. We have developed an approach where ultrathin (= 1 nm) coatings stabilize sulfide SSE powders to aggressively oxidizing atmospheres while significantly improving electrochemical performance. This scalable approach (up to 100 g/batch achieved) enables a new framework for accelerating integration of sulfide SSEs into next-generation solid-state batteries.

Mixing electroactive materials, solid-state electrolytes, and conductive carbon to fabricate composite electrodes is the most practiced but least understood process in all-solid-state batteries. We report on universal halide segregation at interfaces across various halogen-containing solid-state electrolytes and a family of high-energy chalcogen cathodes enabled by mechanochemical reaction during ultrahigh-speed mixing. Bulk and interface characterizations show that the in situ segregated lithium halide interfacial layers substantially boost effective ion transport and suppress the volume change of bulk chalcogen cathodes. Various all-solid-state lithium-chalcogen cells demonstrate utilization close to 100% and extraordinary cycling stability at commercial-level areal capacities.

The next generation of energy storage is being driven by breakthrough solid-state battery technology that overcomes the fundamental limitations of conventional lithium-ion batteries, enabling longer range, faster charging, and enhanced safety through advanced ceramic separator technology. The current challenge facing those developing this technology is commercialization at a global scale to meet the massive global battery demand. This presentation addresses the unique commercialization strategies to bring this technology to market.

Natrion is the manufacturer of Active Separator, a thin, flexible solid-state electrolyte separator for lithium secondary batteries. Natrion will present its latest validation of the performance and safety of semi-solid lithium-metal batteries pairing Active Separator with 5-20 micrometer-thick lithium-metal anodes. This will include cyclability of high-capacity pouch cells at ambient temperatures and pressures (zero clamping) demonstrating 1000+ Wh/L, 400+ Wh/kg energy densities, as well as independent abuse testing results.

This presentation will discuss recent advances in the design of molecular, liquid, and solid‑state electrolytes aimed at enabling high‑voltage lithium batteries with improved safety, stability, and energy density. The talk will highlight strategies to control ion solvation, engineer stable electrode–electrolyte interphases, and mitigate dendrite formation in lithium metal cells. Examples from recent research will illustrate how electrolyte chemistry (e.g. dinitriles, sulfones, ethers) can unlock the performance of next‑generation high‑voltage cathodes and lithium metal anodes.

Battery development calls for tools that will increase the pace of research. The Advanced Electrolyte Model (AEM) is such a tool that is both fast and accurate, owing to its chemical physics platform that covers broad ranges of solvent composition, salt concentration, and temperature. AEM generates over 100 property metrics per run, with typical runs taking less than five seconds to complete. Complex multi-solvent electrolytes can be optimized through AEM using more than a dozen optimization parameters.

CEA’s battery facilities provide a unique framework for scaling up innovative technologies. The battery prototyping and processing laboratory can produce electrodes from small-format to industry-relevant sizes. This integrated approach allows the evaluation of electrochemical performance, but also the assessment of material processability, slurry formulation, and electrode manufacturing compatibility. The value of this scale-up strategy will be illustrated through CEA’s industrial collaboration with TokaiCobex-Savoie, a French producer of synthetic graphite grades.

Binders and additives, though a small part of anode compositions, play a crucial role in achieving a long cycle life. This is especially vital for silicon-containing anodes, where materials like SiOx, Si/C, or Si are employed to enhance storage capacity. Evolving binder chemistries and innovative structural additives, such as Anteo X, aim to minimise inactive materials, pushing silicon anodes forward with significant cycle improvements.

Understanding the structure as well as the underlying degradation mechanism of batteries, is critical for improving performance and longevity. This work leverages advanced AI-powered imaging techniques to reveal structural and chemical information as well as their modification upon cycling. The presented results allow to enhance battery design and stability for Si-based Li-ion batteries and beyond.