US researchers recently reported in the American Chemical Society·Energy News that they have developed a new type of flow battery that stores electrical energy through organic molecules dissolved in neutral pH water. This result makes non-toxic, non-corrosive and long-life batteries possible, and is expected to significantly reduce production costs.
The storage system of the flow battery generally comprises two liquid storage tanks of positive and negative electrodes, and two different electrolytes are installed therein. The connection between these is the power generation area, separated by a diaphragm. The two electrolytes are ion-exchanged between the membranes to achieve storage and release of electrical energy. The larger the reservoir, the more energy is stored.
The flow battery can provide solutions for the storage of renewable energy such as wind power and solar energy, which are discontinuous and unstable in output. However, the existing flow battery will have a reduced storage capacity after multiple charge and discharge cycles, and the electrolyte needs to be maintained periodically. .
Researchers at Harvard University have developed a battery that loses only 1% of storage capacity per 1000 charge and discharge cycles by adjusting the molecular structure of the positive and negative electrolytes to make them soluble in water. Lithium-ion batteries are generally 1000. After the charge and discharge, it cannot be used.
The neutral pH also significantly reduces the manufacturing cost of the separator that separates the positive and negative poles of the battery. Because most of the current flow battery separators use expensive polymers to withstand corrosive substances in the battery, the cost accounts for one-third of the cost of the entire battery equipment. The two sides of the diaphragm in this new flow battery are actually only brine, so its material can be cheap hydrocarbons, which greatly reduces the cost.
Since electrolytes can be dissolved in neutral pH water and are non-toxic and non-corrosive, one can use relatively inexpensive materials to make battery components such as liquid storage tanks and pumps.
Reducing costs is critical to power storage. The US Department of Energy has set a goal to develop batteries that can reduce storage costs per kilowatt per hour to less than $100. If this goal is achieved, then it will store new energy sources such as wind and solar energy that will be comparable to traditional power. Therefore, it can also be said that energy storage technology is the key to the era of new energy.
Imre Jürk, head of energy storage research at the US Department of Energy's Power Office, believes that this research is very important, and it is expected to point the way for future batteries, significantly improve battery life and reduce costs. This highly efficient and durable flow battery is expected Become a standard building block for grid infrastructure.
With the assistance of the Harvard University Technology Development Office, researchers are currently working with several companies to translate this technology into industrial applications. Harvard University has submitted a report to apply for a patent for improved technology for this flow battery.
