University of Surrey engineers have introduced a Lithium-CO2 battery that removes carbon dioxide from the air as part of its normal operation. The upgraded battery design has the potential to outperform its predecessors while helping to combat pollution and climate change. Here’s what you need to know.
Why Lithium-Ion Batteries Fall Short in Green Energy
The future is wireless, and manufacturers understand that there is a demand for clean battery solutions. The most common batteries used today are lithium-ion options. These batteries can be found in everyday devices, such as your cell phone, electric vehicle, and smartwatch. Lithium-ion batteries offer decent density, charge cycles, and are affordable. However, they aren’t sustainable and remain a major pollutant in landfills globally.
Key Challenges of Lithium-Ion Batteries: Safety, Cost, and Waste
There are several problems with lithium-ion batteries that have limited their effectiveness and efficiency. For one, they require the use of expensive, rare-earth materials. Resources like platinum are hard to source and raise the cost of the manufacturing process considerably. Additionally, the demand for rare earth minerals has become a security concern for nations that now seek to ensure they have deep supplies of these essential items.
Lithium-ion batteries also suffer from poor cycle life. The design of this battery incurs some loss for every charge cycle. As such, lithium-ion batteries reduce performance with each cycle. Additionally, they are very expensive to dispose of and can become a safety hazard if improperly charged or if thermal runaway occurs.
Thermal runaway refers to lithium-ion battery cells overheating, causing surrounding cells to do the same. The result is a massive meltdown that can start fires or even explosions. The damage done during these events has been well documented. A simple search will highlight a long history of lithium-ion battery fires across the globe.
Over Potential
Another concern for lithium-ion battery users is overpotential. This term refers to the amount of energy used to start a chemical reaction and charge the battery. Lithium-ion systems suffer from high overpotential. However, all of that is about to change thanks to some ingenuitive scientists.
What Are Lithium-CO₂ Batteries and How Do They Work?
Lithium-CO2 batteries have emerged as an exciting alternative. These rechargeable batteries utilize CO2 gas as an energy carrier. This structure provides some major benefits like improved performance, higher capacity, and cleaner air quality. Consequently, many believe lithium-CO2 batteries are the best step to achieve net-zero carbon emissions in the future.
Drawbacks of Current Lithium-CO2 Batteries
One of the main drawbacks to using Li-CO2 batteries currently is the lack of reliable and low-cost catalysts. Recognizing this fact, engineers have created a new version that integrates recent advancements in material science and computer modeling. The new approach promises to tackle two issues at once, energy use and air quality.
University of Surrey’s Breakthrough Lithium-CO₂ Battery Study
The study1,”Ultralow Overpotential in Rechargeable Li–CO2 Batteries Enabled by Caesium Phosphomolybdate as an Effective Redox Catalyst,” published in Advanced Science, delves into “breathing” batteries. These devices use CO2 to interact with a purpose-built catalyst, creating a clean energy loop.
Lithium-CO2 Batteries Dismantled
As part of their process, the engineers created several Li-CO2 batteries with different catalysts. They then put the batteries through thousands of charge cycles, representing years of daily use. They then dismantled the units after the cycle period to gain a deeper understanding of what occurred in terms of degradation, buildup, and other performance-limiting factors. Notably, the team noticed that lithium carbonate deposits would form and that they could be easily removed to enable the battery to improve its charge cycle.
Lithium-CO2 Batteries Computer Model
The researchers utilized the data they obtained from their experiments to create an accurate computer model. The model uses density functional theory (DFT) to predict critical details and changes. The model enhanced the team’s ability to conduct thought experiments and helped the team reduce total costs while expanding their testing. The goal was to utilize the model to find the best material to create a stable porous structure that could support the chemical reactions that make lithium batteries work.