Clean Cars, but Dirty Batteries?

The raw materials used to fabricate advanced batteries are becoming increasingly important when predicting future market trends. In Guidehouse Insights’ Five Trends for Energy Storage in 2016 and Beyond white paper, improving battery power and energy densities of advanced batteries will come in part by a shift to increased modularity of manufacturing concepts. Not only does this modularity need to occur in energy storage project design, but also in raw material synthesis of battery components. Designing a better battery—especially the (good, yet imperfect) lithium-ion (Li-ion) battery that can address short-term power applications and longer duration energy applications—will be critical for the market to continue to develop.

Increased interest has grown around materials used in advanced battery anodes, and graphite, an allotrope of carbon, is currently one of the leading options due to its abundance in nature, large surface area, and high specific capacity. Current methods of processing natural graphite into coated spherical purified graphite (CSPG), the final product used in battery anodes, can be expensive and harmful to the environment. A consortium of six mining and manufacturing companies are looking to address these issues by jointly acquiring a micronizing and spheronizing mill to produce CSPG. These types of partnerships could push the advanced battery industry forward in developing high-performance electrode materials for next-generation battery technologies.

Improved Performance

Utilizing CSPG in battery anodes leads to improved charge/discharge cycle performance attributed to lower resistance at the anode/electrolyte interface. All companies involved in the partnership have agreed to share their proprietary spheronizing knowledge with each other going forward, with the end goal of meeting cost and capacity targets for Li-ion batteries developed for transportation. Being able to process CSPG locally and efficiently decreases purification times, dramatically improves costs, and significantly reduces environmental impact.

Currently, around 70%-80% of naturally occurring graphite used in batteries is mined and processed in China. It is purified using hydrofluoric acid, a toxic substance that is highly corrosive, dissolving glass and metal surfaces upon contact. Unsustainable methods in place to fabricate batteries and their materials bring rise to questions of whether they are truly a clean alternative and if electric vehicles (EVs) are end-to-end better for the environment. As much as 25 kg of high-purity CSPG is needed to fabricate the anode for one Li-ion EV battery, so ensuring that purification process is as inexpensive and pollution free as possible will be important as demand for these batteries increases.

A Growing Market

The advanced battery market is putting pressure on graphite demand, and improved graphite manufacturing methods means better forecasts for EVs in the future. Guidehouse Insights estimates that light duty plug-in EVs in use will reach over 13.9 million vehicles by 2024 and that Li-ion battery prices will for EVs will drop by over 50% over the same timeframe. Technological improvements of advanced batteries can exceed expectations by better, leaner manufacturing methodologies; more strategic partnerships that further develop the battery’s shortcomings could help foster these improvements while decreasing the environmental footprint.