How 3D Architecture Solves The Cathode Capacity Mismatch In Silicon Anode And Solid-State Batteries?
When we talk of batteries, we talk about performance specifications that vary by product. In the rapidly growing electric vehicle market, more and more customers are requiring high performance across the board: high power (faster charging for EVs) and high energy density (longer range for EVs). The challenge is that with current battery technology, these two objectives cannot be achieved simultaneously. This "power to energy tradeoff" is rooted in the thickness of electrodes: thin electrodes provide high power and thick electrodes yield high energy.
The EV industry uses mostly state-of-the-art Lithium-Ion batteries. The cutting edge advances in EV battery chemistry today encompass the use of silicon as the anode in lithium-ion batteries, and solid-state batteries where in most cases the anode is high energy Li metal. These two advances in anode chemistry are driving market excitement about future high performing batteries. However, today's dominant cathode chemistries - such as the NMC811, NCA, and LFP - are limiting the arrival of these next generation batteries due to one critical factor: the high anode energy levels cannot be matched by the cathode.
Matching Anode And Cathode Capacity Is The Key
It’s accepted by most companies that in order to create next-gen batteries, there is a need to explore new battery chemistries. For the EV industry, the most promising technologies are Solid State (Quantumscape, Solid Power, Ionic Materials, and more) and Silicon anode (SIlaNano, Enovix, Envate, and more). However, these emerging battery chemistries still have some challenges ahead before they go can reach commercial scale such as improving safety, reducing costs, and finding a solution to match the capacities between the anode and cathode. The only solution today to overcome the anode-cathode energy mismatch is to simply use thicker cathodes.
Limitations In Cathode Thickness Is Holding Back The Commercialization of Emerging Chemistries
As a battery 101 refresher, a battery cell is made of an anode and a cathode. The anode charges the ions, while the cathode discharges into the load – which could be anything from a mobile phone to an electric car. Positively-charged ions move from the anode to the cathode through an electrolyte – medium that can conduct ions.
With most cathodes, there’s just not enough ‘space’ to receive the ions. Hence, cathode thickness is a limiting factor that determines battery performance. The obvious solution to this dilemma would be to have batteries with thicker cathodes. Yet, having a thicker cathode will not only increase the size of the battery (which is a hazard in itself) but will also affect the mechanical and thermal stability of the battery. That instability leads to delamination, cracks, separation which eventually leads to a battery failure. As well, as the thickness of cathodes increase, challenges with diffusion limitations and low power capabilities emerge. The result is that there is a practical limit to how thick we can make cathodes, which means there is a limit to how high power we can make our anodes. So where do we go from here?
The Solution Is In The Battery Architecture
3D electrodes can overcome this limiting factor and create the cathodes needed to match anode energy in emerging battery chemistries.
Addionics smart 3D electrodes have higher mechanical stability because of how they’re designed: as a one-piece structured network where the electrolyte is embedded in the current collectors. Cathodes and anodes produced by the new manufacturing process of 3D architecture have shown up to a 14X increase in mechanical stability. This adds to other improved properties of this structure such as greater loading of the active material (to increase energy density), better heat dissipation, 50% lower internal resistance, and more. These resulting advantages remove the present day limitation on the thickness of cathodes, allowing them to match the anode capacity, creating a technical solution that can work for either current or emerging chemistries. The result of switching to 3D chemistry is a high performing battery that is both high power and high energy which is stable and safe to use.
Addionics has developed enhanced battery architectures through the use of Artificial Intelligence and a novel 3D cost-effective manufacturing process, all geared towards one result: creating batteries that are high-power and high-energy. For any type of battery, and especially emerging batteries with high-energy anode chemistries, the 3D architecture solves the critical limiting factor of the anode-cathode energy mismatch .
With the projected cathode market expected to reach $58.8 billion by 2024 and the expected adoption of emerging battery chemistries that will require thicker cathodes, there is a need to transform cathode architecture.
To this end, going smart is the only way out, which is where Addionics comes into the picture. Since our battery architecture enhances battery performance, we aid new and emerging battery chemistries such as silicon, solid-state, and others to be safe, stable, and high-performance. Our smart 3D design will thus accelerate the adoption of better batteries and bring about an electrification revolution to enable a better and more sustainable future.
Find out more in our white paper on How New Battery Design is Transforming the Battery Industry.