University of Texas at Austin Semi-Liquid Battery – Liquid Gel Batteries in Smartphones means Battery life measured in years and not hours

“The greatest significance of our work is that we have designed a semiliquid battery based on a new chemistry. The battery shows excellent rate capability that can be fully charged or discharged almost within one minute while maintaining good energy efficiency and reasonable energy density, representing a promising prototype liquid redox battery with both high energy density and power density for energy storage”

Assistant Professor Dr. Guihua Yu at the University of Texas at Austin discussing his develpement of a Semi-Liquid Battery

Finally, at long last, the developement of Batteries is finally getting some much needed push by scientists in the Research World into the 21-st Century.

A research team from the University of Texas at Austin has recently developed a Semi-Liquid Battery that has the power density of a super-capacitor and can potentially replace Li-Ion Batteries as reported in the article “Semiliquid battery competitive with both Li­ion batteries and supercapacitors”, published 23 May 2015, Physorg.

The team consisting of Assistant Professor Dr. Guihua Yu, along with Dr. Yu Ding and Dr. Yu Zhao recently published their research in an issue of the Journal Nano Letters. The battery, which was specifically designed for use in Hybrid Electric Vehicles and Renewable Energy Storage systems, is composed of a liquid cathode (-), a solid lithium anode (+) and a liquid ferrocene electrolyte.

The result is a Battery that not only can replace Li-Ion Batteries due to their similar voltage but has a storage capacity of a super capacitor and maintains this performance over multiple charge/recharge cycles. Because of its liquid nature, this won't be coming to smartphones anytime soon.

So what makes this Liquid Battery stand out?

University of Texas at Austin Semi-Liquid Battery – Performance by the Numbers

The Researchers semi-liquid battery when constructed looks like your typical Lead Acid battery as shown below. 

The properties of their semi-liquid battery are also impressive:

1.      1400 W/L Power Density

2.      40 Wh/L Energy Density

3.      137 mAh/g Power Storage Capacity

4.      80% of capacity after 500 charge/recharge cycles

These figures for Power Density compares well with Super-capacitors and the Energy Density compares very well most state­of­the­art redox flow batteries and lead­acid batteries, lagging a little behind the performance of Li-Ion Batteries. These figures are best illustrated on the graph below.

The Energy Density is great for Renewable Energy Storage and Backup Battery Systems. If their semi-liquid battery were used as a replacement for Li-Ion Batteries in All-Electric Vehicles, it would improve the All-Electric Vehicles range. They'd also be able to accelerate quicker due to the Higher Power Density, which implies an incredibly high current discharge to power the motors of the vehicle.

Liquid Gel Batteries in Smartphones – Battery life measured in years and not hours

Work, however, still need to be done on Lithium Ion Anode, which gradually breaks down over time into the solution ferrocene solution to quote Dr. Guihua Yu at the University of Texas at Austin:  “The potential weakness of this battery is the lithium anode in terms of long­term stability and safety. More advanced lithium anode protection is required to fully suppress self­discharge”.

Zinc and magnesium further down in the Electrochemical Series are possible replacements, to quote Dr. Guihua Yu at the University of Texas at Austin: We suppose that other metals like zinc and magnesium may also function as the anode for such a battery as long as the electrolyte compatibility is resolved. We also expect that other organometallic compounds with multi­valence­state metal centers (redox centers) may also function as the anode, which eventually would make the battery fully liquid”.

Increasing the solubility of the ferrocene in order to increase the Energy Density is a possibility. Liquid Batteries may one day make smartphone, Tablet and smartwatch batteries that have massive capacities measured in years not days stored in a safe liquid-gel format. Until then, this is progress towards Battery Storage measured in years and months and not just days and hours.

Here’s the link:

Journal Nano Letters