Accompanying the Battery Cell Evolution from Generation to Generation
Consumers want electric vehicles that can travel for hundreds of kilometers and take less than 10 minutes to recharge. Therefore, batteries need to continuously and rapidly evolve in order to meet key electric vehicle industry needs of fast charge and greater autonomy. Today’s lithium-ion batteries must deliver better performance, and higher energy density at lower cost and OEMs are demanding components with high voltage tolerance, high-temperature compatibility, extended cycle life, and simplified processing. The technological evolution is racing ahead as second-generation batteries evolve into third, placing higher requirements on conductive salts, solvents, and additives to incorporate elevated levels of electrochemical resistance. Today, the industry focus is on fourth-generation solid-state batteries which are clearly on the horizon.
With specialized laboratories in battery applications and a strong worldwide Research & Innovation presence, Solvay takes a leading position in creating the right chemistry to help increase battery cell performance. Thanks to our expertise in fluorine chemistry, our unique battery cell solutions portfolio contains key elements for both liquid state and solid-state batteries such as coatings, binders, fluorinated solvents, additives, and lithium salts.
Our Innovative Portfolio Addresses Current and Future Challenges
Through relentless innovation in our dedicated global research centers, we are pushing binder performance to the edge to meet next-generation performance needs. SolgainTM is an intermediate technology that enables the encapsulation of liquid electrolyte inside a polymer matrix. This technology is a bridge between Gen 3 and Gen 4B with advantages in terms of safety, performance, and simplifying the battery manufacturing process.
Generation 4 technology denotes the transition to solid-state batteries. The electrolyte that was liquid in Generation 2 and Generation 3 batteries, encapsulated in a polymer in Solgain® technology, will be replaced by an inorganic electrolyte, therefore without any type of solvent. An inorganic conductive electrolyte that will bring advantages in terms of safety, energy density, cost, and fast charging, thereby responding to all of today’s unmet and partially-met market needs. Solvay is committed to developing critical materials for next-generation inorganic solid-state batteries and pilot research is already underway. Solid-state batteries will deliver a safer future for electric car users with increased range and shorter charging times.
Our broad portfolio with global research and innovation investments makes us the perfect partner to support battery manufacturers’ ambitious targets.
Advanced Materials for Battery Cells
As the industry leader for cathode binders and separator coatings Solef® PVDF ensures excellent adhesion, stability, and safety for durable lithium-ion batteries. Within the electrolyte, our LiFSI and LiTFSI are the market references for lithium salt, and Energain® is our new generation of fluorinated solvents for High Voltage Electrolyte (up to 5V). Battery safety can be increased thanks to TAB, an electrolyte additive that protects rechargeable lithium-ion batteries by reducing the risk of overloading and overheating.
Industry-leading Binders and Separator Coatings
As lithium battery applications continue to evolve, OEMs require binders and separators with more advanced and flexible properties than ever before to facilitate streamlined formulation and manufacturing. Solvay offers PVDF technologies for both LFP and NMC cathode chemistries where our suspension technology can achieve 2x the adhesion level achieved by emulsion technology. Today, Solef® PVDF is the benchmark for cathode binder in the market and is contained in millions of Lithium-ion batteries from a cell phones to the most advanced full battery electric vehicles. Solef® PVDF is also used for separator membranes and coatings, available in a variety of grades, and flexibility to satisfy requirements in a range of applications.
Improving Electrolyte Performance
Conventional conductive salts are often insufficiently conductive at low temperatures so the ions don’t transfer and the battery stops functioning. Our LiFSI, with optimal conductivity at low temperatures, allows the battery to function up to -30°C, a key requirement for EVs. LiFSI is also stable at high temperatures which is important in situations of repeated acceleration and in resistance to high temperatures in fast charging.
Solvay is a global leader in advanced fluorinated technology (LiTFSI) which is based on a unique, sustainable, integrated, and competitive patented production process. Thanks to its high ionic conductivity and excellent chemical/thermal stability, LiTFSI is a key component for Li-ion batteries in liquid electrolytes as well as solid electrolytes (LMP batteries).
The surge of high manganese cathodes is also triggering the need for high voltage resistance solvents for electrolytes so Solvay is introducing a new Energain® solvent with unique resistance to voltages up to 4.9 volts.
Fluorinated Compounds and Derivatives
The use of fluorine has become a key element in the electrolyte of Li-Ion batteries. Solvay offers high purity, low moisture TAB (tert-amylbenzene) additives that give overcharge protection up to 5V. These materials help achieve improved battery safety, energy storage, longer cycle life, and overcharge protection, all critical requirements for next-generation batteries.
Energain® Technology for High Voltage Electrolytes
Achieving high energy density at an affordable price without compromising safety is one of the key unmet needs of the battery industry. Energain® is the new generation of fluorinated solvents and formulations for High Voltage Electrolyte (up to 5V). Energain® technology opens the door to the stabilization of unprecedented high-voltage systems with a large variety of cathodes (LCO, Ni-rich NCM, LMNO), addressing the challenges of tomorrow’s batteries and reaching the full potential of advanced Li-ion technology.