Sodium-sulfur cell

Abstract

The invention discloses a sodium-sulfur cell in the chemical energy storage field. The sodium-sulfur cell comprises a shell and an electrolyte ceramic tube nested inside the shell. An anode chamber radially forms between the shell and the electrolyte ceramic tube. A cathode chamber radially forms inside the electrolyte ceramic tube. The anode chamber is filled with a porous conducting fiber felt. The top of the electrolyte ceramic tube is provided with a ceramic insulating ring radially projecting out. An anode seal is disposed between the ceramic insulating ring and the shell and closes the anode chamber. A sodium storage tube and a safety tube connected to the outside of the sodium storage tube in a sleeving manner are disposed inside the cathode chamber. The top of the sodium storage tube is closed through a cathode seal cap. A cathode seal ring is disposed between the ceramic insulating ring and the cathode seal cap and closes the cathode chamber. An insulated buffer layer non-wettable to liquid sodium is disposed between the bottom of the outer wall of the safety tube and the bottom of the inner wall of the electrolyte ceramic tube. The bottom of the outer wall of the electrolyte ceramic tube is provided with an insulated bottom protection layer non-wettable to sulfur and sodium polysulfide.

Description

technical field [0001] The invention relates to a sodium-sulfur battery in the field of chemical energy storage. Background technique [0002] like figure 1 As shown, the sodium-sulfur battery includes a casing 1 and an electrolyte ceramic tube 4 sleeved in the casing 1 . A positive electrode chamber 100 is formed between the casing 1 and the electrolyte ceramic tube 4 , and the positive electrode chamber 100 is filled with porous conductive fiber mats 2 . A ceramic insulating ring 3 protruding radially outward is provided on the top surface of the electrolyte ceramic tube 4 to seal the positive electrode chamber 100 . The negative electrode chamber 400 is formed inside the electrolyte ceramic tube 4 . The negative electrode chamber 400 is provided with a sodium storage tube 9 and a safety tube 8 sleeved on the outside of the sodium storage tube 9 . The bottom of the sodium storage tube 9 is provided with a through hole 91 , and the top of the sodium storage tube 9 is cl...

AI Technical Summary

Problems solved by technology

Once the electrolyte ceramic tube 4 has microcracks or breaks, the direct contact between sodium and sulfur will cause a violent reaction, and the temperature can reach up to 2000°C, instantly melting all the components in the sodium-sulfur battery, resulting in the leakage of active materials

The safety protection structure of the existing sodium-sulfur battery mainly adopts a safety tube 8 that is socketed between the electrolyte ceramic tube 4 and the sodium storage tube 9 and has a large expansion coefficient with the electrolyte ceramic tube 4. The safety tube 8 is usually made of aluminum or aluminum alloy. , the radial gap 401 between the safety tube 8 and the inner wall of the electrolyte ceramic tube 4, the width of the radial gap 401 is controlled at 100 microns, when the electrolyte ceramic tube 4 is damaged, the safety tube 8 axially expands to be close to the electrolyte ceramic tube 4 inner wall, and give the inner wall of the bottom of the electrolytic ceramic tube 4 a pressure, which is greater than the pressure on the outer wall of the bottom of the electrolytic ceramic tube 4, and the radial gap 401 between the safety tube 8 and the electrolytic ceramic tube 4 also follows the pressure of the safety tube 8 The radial expansion of the closed, sodium and sulfur can not access

This protection method has high requirements on the verticality of the electrolyte ceramic tube 4 and the roundness of the bottom of the electrolyte ceramic tube 4, so processing the electrolyte ceramic tube 4 is time-consuming and laborious, and at the same time, the electrolyte ceramic tube 4 is easily damaged during use.

Images