Lithium ion batteries are flammable and the price of the raw material is rising. Are there alternatives? Yes: Empa and ETH Zürich researchers have discovered promising approaches as to how we might produce batteries out of waste graphite and scrap metal.
Kostiantyn Kravchyk works in the group of Maksym Kovalenko. This research group is based at both ETH Zurich and in Empa’s Laboratory for Thin Films and Photovoltaics. The two researchers’ ambitious goal at the Empa branch is to make a battery out of the most common elements in the Earth’s crust – such as magnesium or aluminum. These metals offer a high degree of safety, even if the anode is made of pure metal. This also offers the opportunity to assemble the batteries in a very simple and inexpensive way and to rapidly upscale the production.
In order to make such batteries run, the liquid electrolyte needs to consist of special ions that do not crystallize at room temperature – i.e. form a kind of melt. The metal ions move back and forth between the cathode and the anode in this “cold melt”, encased in a thick mantle of chloride ions. Alternatively, large but lightweight organic anions, which are metal-free, could be used. This does come with a problem, though: where are these “thick” ions supposed to go when the battery is charged? What could be a suited cathode material? By way of comparison: in lithium ion batteries, the cathode is made of a metal oxide, which can easily absorb the small lithium cations during charging. This does not work for such large ions, however. In addition, these large anions have an opposite charge to the lithium cations.
Battery turned “upside down”
To solve the problem, Kovalenko’s team had a trick up their sleeves: the researchers turned the principle of the lithium ion battery upside down. In conventional Li-ion batteries, the anode (the negative pole) is made of graphite, the layers of which (in a charged state) contain the lithium ions. In Kovalenko’s battery, on contrary, the graphite is used as a cathode (the positive pole). The thick anions are deposited in-between the graphene layers. In Kovalenko’s battery, the anode is made of metal.
Kravchyk made a remarkable discovery while searching for the “right” graphite: he found that waste graphite produced in steel production, referred to as ”kish graphite”, makes for a great cathode material. Natural graphite also works equally well – if it is supplied in coarse flakes and not ground too finely or into folded, non-flake shapes. The reason: the graphite layers are open at the flakes’ edges and the thick anions are thus able to slip into the structure more easily. The fine-ground graphite normally used in lithium ion batteries, however, is ill-suited for Kovalenko’s battery: by grinding the graphite particles, the layers become creased like crumpled-up paper. Only small lithium ions are able to penetrate this crumpled graphite, not the new battery’s thick anions.
The graphite cathode battery constructed from steel production “kish graphite” or raw, natural graphite flakes has the potential to become highly cost-effective. And if the first experiments are anything to go by, it is also long-lasting. For several months, a lab system survived thousands of charging and discharging cycles. “The aluminum chloride – graphite cathode battery could last decades in everyday household use,” explains Kravchyk and adds “similar demonstrations, but further increased battery voltages, without compromising capacities, and of even lighter elements are on the way and will offer further increase in energy densities from current 60 Wh kg-1 to above 150 Wh kg-1”
Learn more: Low-cost battery from waste graphite
The Latest on: Low-cost battery
- Williams Advanced Engineering teases low-cost lightweight compositeson May 11, 2020 at 8:45 pm
What was once the offshoot of a Formula One team is now forging quite a separate path for itself. Williams Advanced Engineering is channeling its Formula E experience to focus quite heavily on two ...
- BLM and DOI Issue Final Record of Decision for Milestone 690MW Gemini Solar and Battery Storage in Nevadaon May 11, 2020 at 3:43 pm
Quinbrook Infrastructure Partners is pleased to announce that the BLM and DOI have issued the final ROD for the Gemini Solar + Battery Storage Project ...
- Holy grail of big batteries – first pilot for Gates-backed battery with 150 hours storageon May 10, 2020 at 3:33 pm
US utility to pilot “aqueous air flow” battery – backed by group including Bill Gates and Macquarie Capital – that promises to deliver 150 hours of storage at very low cost.
- U.S. Lead Acid Battery Market is Projected to Grow $14.4 Billion with CAGR of above 5.3% by 2025 | Grand View Research, Inc.on May 10, 2020 at 5:25 am
Market Research And Consulting.” According to report published by Grand View Research, The U.S. lead acid battery market ...
- Power Management IC Boosts Battery Life Up to 20% in Wearableson May 8, 2020 at 12:23 pm
Maxim Integrated said the chipset integrates up to 40% of the power management parts used in wireless earphones and other wearables. That reduces the bill of materials by nearly 25% while boosting the ...
- In a potential big win for renewable energy, Form Energy gets its first grid-scale battery installationon May 7, 2020 at 8:25 pm
Form Energy, which is developing what it calls ultra-low-cost, long-duration energy storage for the grid, has signed a contract with the Minnesota-based Great River Energy to develop a 1 megawatt, 150 ...
- Low-Cost Power Efficient Haptic Device for VR Invented at Carnegie Mellonon May 6, 2020 at 5:57 am
The device weighs less than 10 ounces, and Fang and her fellow researchers from Carnegie Mellon estimate that the cost per unit would equal less than $50.
- India's Electric Rickshaw Battery Market by Vehicle, Battery Capacity and End-use - Forecast to 2024on May 1, 2020 at 4:00 am
The "India Electric Rickshaw Battery Market Research Report: By Vehicle, Battery Capacity, End Use - Industry Size, Trend, Growth and ...
- Zinc8 Energy Solutions advancing low-cost battery and forging new market amid changing energy worldon April 30, 2020 at 4:00 am
The global rise in electricity from renewable sources has led to increased demand for advanced batteries that can be used to firm intermittent supply ...
- New Mexico Regulators Defer Decision on Solar-Battery Planon April 29, 2020 at 11:53 am
New Mexico regulators are putting off a decision on a proposal by the state's largest electric provider to build two hybrid solar-battery storage facilities even though bids for the projects were set ...
via Google News and Bing News