>
What are solid-state batteries?
What are solid-state batteries?
In solid-state batteries, both electrodes and the electrolyte consist of solid material. Although some solid-state batteries are already in use in electric cars or trucks (e.g. in the “Bollore Blue Car”), most are currently still under development.
The advantages of all-solid-state batteries (ASSB) over the common liquid electrolyte batteries are the replacement of the (usually highly flammable) liquid electrolyte by a solid electrolyte. Furthermore, solid-state batteries have a higher energy density and a faster charging capacity, which is an important property for the rise in electromobility.
Different materials such as polymers, metals and ceramics are used in various combinations for solid-state batteries.
What are liquid electrolyte batteries?
Liquid electrolyte batteries have been used for many years and are currently the most commonly used batteries, e.g. lithium ion batteries (LIB) in mobile phones. In liquid batteries, the electrolytes are present in dissolved form, but the electrodes are made of a solid material. The liquid electrolytes are usually highly flammable, which is often seen as a disadvantage. Therefore, solid-state batteries are currently being developed in which the electrolytes are in solid form.
What types of liquid electrolytes are there?
Liquid electrolytes are mostly water-based salt solutions consisting of organic and inorganic acids. However, simple saline solutions can also be used.
What types of rechargeable batteries (secondary batteries) are there and where are they used?
There are a variety of rechargeable batteries or secondary batteries, which can be roughly divided into liquid electrolyte batteries (also called wet cell) and solid-state batteries. Generally, they consist of 2 electrodes and an electrolyte, each of which can be made of different materials.
The majority of batteries in use today and in the near future are liquid electrolyte batteries, mainly lithium ion batteries.
Some solid-state batteries are already in use, most others are currently in basic research. Materials used are, for example, sodium, magnesium or aluminium.
What is the difference between perovskite and conventional solar cells?
Conventional solar cells are often made of silicon dioxide, which is used in amorphous or crystalline form. It takes a lot of know-how and money to produce it, and the yield of light energy conversion in commercial products is less than 25% [1]. Therefore, solar cells are also made from other elements. Among the most prominent representatives here are GaAs (gallium arsenide), CdTe (cadmium tellurium) and CIGS (copper indium gallium selenium) solar cells. These elements are controversial, as some are e.g. toxic, only difficult to obtain from socially / ethically acceptable sources and usually very expensive.
Therefore, sustainable alternatives are being sought: perovskite solar cells could be cheaper to produce and the starting materials easier to obtain. However, they also contain toxic elements (status 2022). Intensive research is therefore being conducted into less toxic perovskite solar cells. Good luminous efficiencies have already been achieved in the laboratory, and in particular the possibility of building semi-transparent cells could lead to very high yields in light energy conversion if perovskite and conventional solar cells are arranged one above the other (tandem solar cell or multi-junction solar cell).
Further infomation
- US National Renewable Energy Laboratory (NREL) – Best Research-Cell Efficiency Chart