Electrochemical cell
There are generally two main types of electrochemical cells: primary (non-rechargeable) and secondary (rechargeable) batteries.
A galvanic cell also called a voltaic cell, is an electrochemical cell in which an electric current is generated from an oxidation-reduction reaction. The cell normally consists of two different metals (electrodes), immersed in separate containers that hold a positively or negatively charged solution. A salt bridge or porous membrane between the containers transfers charge. Energy is derived from a high-cohesive-energy metal dissolving while to a lower-energy metal is deposited, and/or from high-energy metal ions plating out while lower-energy ions go into solution. A primary or non-rechargeable battery is a galvanic cell, a secondary or rechargeable battery acts as a galvanic cell when it is discharging, as it is converting chemical energy to electrical energy. A secondary or rechargeable battery acts as an electrolytic cell when it is being charged as in this case it is converting electrical energy to chemical energy.
An electrolytic cell, is one in which a current is passed through by an external voltage, causing a chemical reaction. An electrolytic cell has three parts: a cathode, an anode (electrodes) and an electrolyte. As above electrolyte is usually a solution of water or another solvent, such as sodium chloride with dissolved ions. When an external voltage is applied to the electrodes, the ions in the electrolyte are attracted to an electrode with the opposite charge, the charge-transferring causes the chemical reaction, faradaic or redox. In the galvanic cell the chemical reaction causes electric current to flow.
An equilibrium electrochemical cell is a cell that sits in a state that is directly between the two above cell states, so nether storing chemical energy nor releasing electrical energy.
A fuel cell is considered to be a galvanic cell but because the products of the reaction are continuously removed it is one that requires a supply of reactants. It does not therefore store chemical or electrical energy but extracts electrical energy directly from a chemical reaction involving oxygen, hydrogen, electricity, heat and water.
[edit] Related articles on Designing Buildings
Featured articles and news
Provisional findings show illegal cartels in the industry.
CIAT reporting from the Competition and Markets Authority.
Making sustainable construction number one priority.
The future of construction report.
Interview with ECA CEO.
Many provisions came into force on June 28, 2022.
With room to expand.
An information packed session at the BSRIA conference.
Refurbishment, Energy Efficiency, Indoor air and process.
Considering building acoustics with the AT Journal.
Why building acoustic considerations must be non-negotiable.
Create a profile, write informed product articles and share.
Aluminium Composite Panels (ACP) is one example.
Top 50 Women in engineering 2022.
Inventors and innovators at ICE.
Life, death and art at the Stuart court. Book review.
Real estate, place adaptation and innovation.
Review and comment on the revised draft before July 11.
We are indeed now 10 years old, so go on and be bold !
Write about something you know, help us build and grow !
IHBC's 25th anniversary 2022 Aberdeen School.
A blended event and triumphant return.
New Construction Leadership Council Co-Chair selected.
Mark Reynolds succeeds Andy Mitchell as Co-Chair of CLC
Designing Buildings is 10 years old.
Types of work to existing buildings.
From alteration to deconstruction on DB.
Publication available
Changes come into force for F,L,O and S.