Battery developers face some difficult challenges when designing these electrochemical cells. Depending on battery usage and application, these challenges include:
- Energy and power density
- Battery life
- Costs
- Sustainability
Modeling and simulation are two current methods that researchers and developers use to test and improve such issues. Optimization of each component of a battery and battery system—such as the electrolyte, electrodes, and separator—can be accelerated using modeling and simulations. For example, the Fiat Research Center applies mathematical modeling to study the thermal management of container cells for its hybrid vehicles.
Advancing future battery designs will require detailed analysis of each of these key elements…
Energy density is restricted by battery chemistry and design. The chemistry is defined by the electrode material and the structure of the electrolyte. For example, lithium-air batteries offer great potential for efficient energy storage applications due to their extremely high theoretical energy density. However, there are still technical limitations to consider before its safe implementation, such as the components required for thermal management and the weight of the battery.
Furthermore, the power density of a battery is necessary for some applications, especially for the efficiency of electric vehicles. High power density is necessary when recovering energy in a short period of time, such as through regenerative braking or rapid recharging. This means that the battery must handle high current densities during recharging and relatively low current frequencies during discharge. Battery components, including electrodes, separator and electrolytes, are extremely important for power density.
Battery life is critical to optimizing applications and significant when safety and reliability are involved. Ideally, battery discharge, use, and failure should occur slowly and in a controlled, transparent process. Uneven distribution of current density and inadequate control of discharge and recharge cycles, as well as thermal management, can increase wear and tear and increase the risk of failure. Short circuits created by metal deposition can also decrease productivity and increase uncontrolled heating.
The operating capacity of a lithium-ion battery storage system, for example, is determined by the type of lithium-ion chemistry used, combined with the number of battery cells in the total battery bank. There are many factors to consider.
Health monitoring technologies are needed to continually assess battery system status and chances of failure.
Costs for batteries have decreased considerably over the past decade. A report published by Bloomberg New Energy Finance (BNEF) late last year indicated that battery prices have fallen from US$1,100/kWh ($A1,609) since 2010, and are expected to reach close to the US$100/kWh mark. kWh ($A146) by 2023. This is good news for the electric vehicle market because it means EV costs will be equivalent to internal combustion engine vehicles.
According to Bloomberg, this is largely due to increased order sizes, but also the use of high-energy density cathodes and improved packaging designs.
However, the manufacturing methods of high-power batteries are still relatively high. Therefore, there is significant potential for productivity gains through large-scale manufacturing processes of battery elements.
Sustainability has become a critical topic in the design of new batteries. There is pressure particularly on the electric vehicle industry to figure out recycling and avoid unnecessary waste of batteries after their useful life. Therefore, it is important that manufacturers and governments provide a plan for mining, recycling, producing and disposing of new battery models whenever possible.
