The transition of the global economy to widespread electrification has increased the demand for longer-lasting, faster-charging batteries in industries such as transportation, consumer electronics, medical devices, and household energy storage. While the benefits of this transition are known, in reality battery innovation has not kept pace with society’s ambitions.
With Reports that predict a 40% probability that the world temperature will rise above the limit of 1.5 degrees Celsius set in the Paris Climate Agreement in the next five years, it is clear that little time is to be lost in the development of next-generation batteries, which can easily last another 10 years to full commercialization.
To cope with increasing electrification pressures, a completely new approach to building batteries is the only way to scale rechargeable batteries fast enough to curb greenhouse gas emissions worldwide and avoid the worst-case scenario of the climate crisis.
The challenges of battery innovation
Over the past few decades, battery experts, automakers, tier 1 suppliers, investors, and others looking to electrify have spent billions of dollars developing next-generation batteries around the world, primarily focusing on battery chemistry. However, the industry is still grappling with two major fundamental engineering challenges that are holding back the spread of batteries:
- Compromise between energy and performance: All batteries manufactured today must compromise between energy and performance. Batteries can store more energy or you can charge / discharge faster. For electric vehicles, this means that no single battery can offer both long range and fast charging.
- Anode-cathode mismatch: Today’s most promising battery technologies maximize the energy density of anodes, the negative electrode of the pair of electrodes that make up each lithium-ion battery cell. However, anodes already have a higher energy density than their positive counterpart, the cathode. The energy density of the cathode must ultimately match that of the anode in order to get the most energy storage capacity out of a given battery size. Without breakthroughs in increasing cathode energy density, many of today’s most exciting battery technologies will not reach their full potential. The lithium-ion battery that is currently most frequently used cannot meet the diverse applications of a fully electric future. Many companies have tried to meet these needs through new battery chemistries to optimize the high power to energy density ratio with varying degrees of success, but very few are close to achieving the performance metrics required for mass production and commercialization.
Ultimately, the winning technologies in the race for full electrification will be those that have the greatest impact on performance, cost reduction and compatibility with existing manufacturing infrastructure.
Are Solid State Batteries the Holy Grail?
Battery researchers have advocated the solid-state battery as the holy grail of battery technology because of its ability to achieve high energy density and increased safety. Until recently, however, the technology was neglected in practice.
Solid-state batteries have a significantly higher energy density and are potentially safer because they do not use flammable liquid electrolytes. However, the technology is still in its infancy and has a long way to go to reach commercialization. The solid-state battery manufacturing process needs improvement to drive costs down, especially for an automotive industry that seeks aggressive cost reductions of up to $ 50 / kWh in the coming years.
The other major challenge in implementing solid-state technology is limiting the total energy density that can be stored in the cathodes per unit volume. The obvious solution to this dilemma would be batteries with thicker cathodes. However, a thicker cathode would reduce the mechanical and thermal stability of the battery. This instability leads to delamination (a type of failure where a material breaks into layers), cracks, and delamination – all of which lead to premature battery failure. In addition, thicker cathodes limit diffusion and reduce performance. The result is that the thickness of the cathodes is practically limited, which limits the performance of the anodes.
New materials with silicone
In most cases, companies developing silicon-based batteries mix up to 30% silicon with graphite to increase energy density. The batteries of Sila nanotechnologies are an illustrative example of the use of a silicon mixture to increase energy density. Another approach is to use anodes made of 100% pure silicon, limited by very thin electrodes and high production costs, in order to produce an even higher energy density, such as e.g. amp Approach.
While silicon offers a significantly higher energy density, there is a significant disadvantage that has so far limited its acceptance: the material expands and shrinks in volume during charging and discharging, which limits the service life and performance of the battery. This creates degradation problems that manufacturers must resolve prior to commercial launch. Despite these challenges, some silicon-based batteries are already in commercial use, including in the automotive sector, where Tesla is leading the way in introducing silicon for electric vehicles.
The need for electrification calls for a new focus on battery design
Advances in battery architecture and cell design hold promise for improvements in existing and emerging battery chemistries.
Probably the most notable from a mainstream perspective is Tesla’s “cookie-tin” battery cell, which the company unveiled at its 2020 Battery Day. It still uses lithium-ion chemistry, but the company has removed the tabs in the cell that act as the positive and negative connection points between the anode and cathode and the battery case, and instead uses a shingled design within the cell. This design change helps reduce manufacturing costs while increasing range, and removes many of the thermal barriers a cell can encounter when fast charging with direct current.
Moving from a traditional 2D electrode structure to a 3D structure is another approach that is gaining traction in the industry. The 3D structure provides high energy and high performance in both the anode and cathode for any battery chemistry.
Although the 3D electrodes are still in the R&D and test phase, they have twice the available capacity, a 50% shorter charging time and a 150% longer service life for high-performance products at fair market prices. Therefore, in order to improve battery capacities to realize the full potential of energy storage for a range of applications, it is critical to develop solutions that focus on changing the physical structure of batteries.
Win the battery race
It’s not just performance gains that win the battery race, but also perfecting production and cutting costs. Capture a significant portion of the balloon battery market that is expected to be reached $ 279.7 billion by 2027, countries around the world need to find ways to achieve low-cost, large-scale battery manufacture. Prioritizing drop-in solutions and innovative production methods that can be integrated into existing assembly lines and materials will be critical.
The Biden Administration American job plan Underlines the importance of domestic battery production for the country’s goal of leading the way in electrification while at the same time achieving ambitious targets for CO2 reduction. Commitments like these will play a key role in determining who can claim a critical competitive advantage in the battery space and hold the largest share of the market the global electric vehicle market of $ 162 billion.
Ultimately, the winning technologies in the race for full electrification will be those that have the greatest impact on performance, cost reduction and compatibility with existing manufacturing infrastructure. By taking a holistic approach and focusing more on innovative cell design while refining leading chemistries, we can take the next steps in battery performance and rapid commercialization that the world desperately needs.