Related Experiment Video
Updated: Jun 2, 2026
10:03
Characterization of Electrode Materials for Lithium Ion and Sodium Ion Batteries Using Synchrotron Radiation Techniques
Published on: November 11, 2013
Increasingly Reversible Na/Cl2 and Li/Cl2 Batteries
Guanzhou Zhu1, Hongbin Xu2,3, Shuo Wang4
1Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States.
Journal of the American Chemical Society
|June 1, 2026
Summary
Researchers developed novel sodium/chlorine and lithium/chlorine batteries using cobalt polyphthalocyanine electrodes. These high-energy-density batteries demonstrate stable cycling exceeding initial capacity, paving the way for advanced energy storage solutions.
Area of Science:
- Electrochemistry
- Materials Science
- Energy Storage
Background:
- Sodium/chlorine and lithium/chlorine batteries offer high voltage and capacity.
- Developing high-energy-density batteries is crucial for real-world applications.
- Existing chlorine battery technologies face challenges in stability and efficiency.
Purpose of the Study:
- To investigate cobalt polyphthalocyanine as a positive electrode material for sodium/chlorine and lithium/chlorine batteries.
- To achieve stable cycling capacity exceeding the first discharge capacity in chlorine batteries.
- To elucidate the electrochemical mechanisms governing the performance of these novel battery systems.
Main Methods:
- Synthesis of cobalt polyphthalocyanine on multiwalled carbon nanotubes.
- Electrochemical characterization including cycling tests and impedance spectroscopy.
- Theoretical calculations and various analytical techniques (e.g., X-ray diffraction, spectroscopy) to understand reaction mechanisms.
Main Results:
- Cobalt polyphthalocyanine enables stable cycling capacity exceeding the first discharge capacity in chlorine batteries.
- Facilitates formation of electrochemically active submicron-sized sodium chloride crystals.
- Enhances chlorine/chloride redox reversibility through cobalt-chlorine and sodium-nitrogen bond formation.
- Acts as an effective storage medium for chlorine during charging.
- Demonstrated tunability by varying metal center (Co to Fe) and carbon substrate (MWCNT to graphite).
- Achieved a sodium/chlorine battery with an energy density of ~150 Wh kg⁻¹ or ~325 Wh L⁻¹ operating with minimal electrolyte.
Conclusions:
- Cobalt polyphthalocyanine is a promising electrode material for high-performance sodium/chlorine and lithium/chlorine batteries.
- The material enhances electrochemical activity, redox reversibility, and chlorine storage.
- These advancements enable the development of high-energy-density chlorine batteries with reduced electrolyte requirements.
Related Concept Videos
03:12Batteries and Fuel Cells
A battery is a galvanic cell that is used as a source of electrical power for specific applications. Modern batteries exist in a multitude of forms to accommodate various applications, from tiny button batteries such as those that power wristwatches to the very large batteries used to supply backup energy to municipal power grids. Some batteries are designed for single-use applications and cannot be recharged (primary cells), while others are based on conveniently reversible cell reactions that...
01:24Types of Reversible Electrodes
For electrode reversibility to be maintained, all the reactants and products involved in the half-reaction must be present at the electrode. There are several types of reversible electrodes (half-cells).In metal-metal-ion electrodes, a metal balances electrochemically with a solution of its own ions. Examples are Cu2+|Cu and Zn2+|Zn. Metals that react with the solvent, like group 1 and most group 2 metals, which react with water, and zinc, which reacts with aqueous acidic solutions, cannot be...
02:48Ionic Bonding and Electron Transfer
Ions are atoms or molecules bearing an electrical charge. A cation (a positive ion) forms when a neutral atom loses one or more electrons from its valence shell, and an anion (a negative ion) forms when a neutral atom gains one or more electrons in its valence shell. Compounds composed of ions are called ionic compounds (or salts), and their constituent ions are held together by ionic bonds: electrostatic forces of attraction between oppositely charged cations and anions.
01:24Electrochemical Systems
Electrochemical systems provide a fascinating insight into the dynamic interplay of charged species within various phases. One notable example is the interaction between a membrane permeable to K⁺ ions but not to Cl⁻ ions, separating an aqueous KCl solution from pure water. As K⁺ ions diffuse through the membrane, they generate net charges on each phase, leading to a potential difference between them.Similarly, when a piece of Zn is immersed in an aqueous ZnSO₄ solution, the Zn metal, composed...
03:00Electrolysis
In a galvanic cell, the electrical work is done by a redox system on its surroundings as electrons produced by the spontaneous redox reactions are transferred through an external circuit. Alternatively, an external circuit does work on a redox system by imposing a voltage sufficient to drive an otherwise nonspontaneous reaction in a process known as electrolysis. For instance, recharging a battery involves the use of an external power source to drive the spontaneous (discharge) cell reaction in...
02:21Electrolyte and Nonelectrolyte Solutions
Substances that undergo either a physical or a chemical change in solution to yield ions that can conduct electricity are called electrolytes. If a substance yields ions in solution, that is, if the compound undergoes 100% dissociation, then the substance is a strong electrolyte. Complete dissociation is indicated by a single forward arrow. For example, water-soluble ionic compounds like sodium chloride dissociate into sodium cations and chloride anions in aqueous solution.