Toshiba: Newly developed “non-burning” LiB: Aqueous Lithium-ion Battery
-Realization of cost reduction-
Toshiba:
November 19, 2020
The company announced that it has developed the world’s first “water-based lithium-ion secondary battery (hereinafter, water-based battery) that can be operated even at -30 ° C.”
It is a battery that uses water as the electrolyte, and is characterized by being safe even in the event of a fire caused by an external factor.
Aim for early sample proposals in the future.
Spread of renewable energy:
With the widespread use of renewable energy such as solar power generation, the demand for storage batteries is increasing in order to absorb output fluctuations that are affected by the weather.
Lithium-ion secondary battery:
Lithium-ion secondary batteries are often used as storage batteries.
However, it is necessary to maintain a high voltage of 3.7V or higher.
Therefore, a flammable organic solvent is generally used as the electrolytic solution.
Water-based lithium-ion secondary battery:
A water-based lithium-ion secondary battery developed by Toshiba this time.
For the negative electrode, “non-burning lithium titanium oxide (LTO), not graphite” is used. ..
In addition, to improve safety
Considering the safety in the event of a fire caused by an external factor,
A nonflammable aqueous solution was used as the electrolytic solution.
Conventional water-based batteries:
Conventional aqueous batteries undergo an “electrolysis reaction of an aqueous solution” when operated for a long period of time.
Therefore, the problem was that the charge / discharge reaction did not proceed.
Toshiba water-based batteries:
Toshiba has developed a unique battery structure that combines a “high-concentration electrolyte with a high concentration of lithium salts” and a “solid electrolyte separator”.
By “preventing the movement of hydrogen ions from the positive electrode side to the negative electrode side”, the electrolysis of the aqueous solution was suppressed.
as a result:
“Achieves charging and discharging more than 2000 times, which is 10 times that of the conventional technology”
Also,
“Achieved a high voltage of 2.4V for water-based batteries”
further,
Using an aqueous solution that does not freeze even at low temperatures, it has become possible to charge and discharge even at -30 ° C.
Field of use:
Does not contain combustibles and does not fall under the Fire Service Act dangerous goods,
Safety measures can be simplified more than before,
In addition, the installation location restrictions will be relaxed, so
It can be installed near a residence or in an office building.
By using water as the electrolyte, “cost reduction by simplifying manufacturing equipment” can be expected.
Smart Japan
https://www.itmedia.co.jp/smartjapan/articles/2011/20/news067.html
Toshiba Develops World ’s First Aqueous Lithium-ion Battery with Nonflammable Electrolyte
-Greater freedom in locating large-scale stationary energy storage systems expected to contribute to stable management of renewable energy sources and realization of a decarbonized society-
November 19, 2020
Toshiba Corporation (TOKYO: 6502)
has developed a prototype aqueous rechargeable lithium-ion battery
that points the way to realization of the world’s first aqueous large-capacity stationary storage battery that can operate at -30 ° C.
Countering climate change and reducing greenhouse gas emissions
will require greater reliance on renewable energy sources that are characterized by intermittent availability, and maximized utilization will only be possible with management systems integrating storage batteries that are safe and reliable over the long-term.
Toshiba has addressed this concern by developing a battery cell that uses water as the aqueous electrolyte.
The battery demonstrates low risk over the long term, even in the event of exposure to fire, which expands the range of locations where it can be installed.
It also delivers the high durability of over 2,000 charge and discharge cycles, a performance that can contribute to expanded use of renewable energy.
Details of the technology
will be presented online at the 61st Battery Symposium in Japan on November 19, 2020.
The sun and wind are gradually important renewable power generation sources worldwide, crucial for advancing de-carbonization.
However, unlike fossil fuel power sources, output from renewables fluctuates with the time of day, weather, season and location, and achieving a stable supply requires the deployment of large-scale stationary batteries to regulate output.
The batteries used in these systems
are lithium-ion rechargeable batteries (LIB), as they exhibit high energy density.
However, a major issue with LIB is safety. LIB achieves their high energy density by using a flammable organic solvent with a wide stable voltage window as the electrolyte.
This flammability often restricts where storage batteries ca be installed.
Guaranteeing high-level safety is a major concern because large-scale stationary storage batteries must be operated for a long period of time.
Toshiba ’s SCiB ™
achieves excellent safety performance by replacing the usual graphite anode with a nonflammable lithium titanate oxide (LTO).
Moving beyond this, the company has further boosted safety by developing a battery that uses an aqueous electrolyte.
While the LTO
secures the battery against shock and vibration, the aqueous electrolyte ensures safety in the event of a fire at the installation location.
This advance both simplifies the safety
measures necessary during installation, and broadens the scope of locations where systems can be installed.
It is now possible to consider installation near residential areas and inside office buildings, a factor that will contribute to more widespread use of large-scale storage batteries.
Toshiba Corporate Research & Development Center: