Details
sulfide solid-state electrolyte, lithium phosphorus sulfur chloride Li5.5PS4.5Cl1.5 is used in solid-state lithium batteries. sulfur replaces oxygen in sulfide solid-state electrolyte. on the one hand, it increases the unit cell volume, expands the size of Li transmission channel, weakens the attraction and binding of Li by the structure, and increases the carrier concentration. therefore, the ionic conductivity of sulfide in several solid-state electrolytes is relatively high, and the doping ratio of chlorine is increased compared with Li6PS5Cl, the ionic conductivity is further improved. On the other hand, however, toxic gases are easily generated, and the wet air stability needs to be improved.
ionic conductivity test of sulfide electrolyte powder:
1. the ionic conductivity test value of sulfide solid electrolyte powder increases with the increase of tabletting pressure, and the ionic conductivity tends to be stable above 400MPa, and even the test value may be inaccurate due to internal cracking and delamination of the tablet caused by excessive pressure. Therefore, the pressure of 200 ~ 400MPa is generally used.
2. the cold-pressed blank uses a stainless steel column as the blocking electrode, and the electrode can be in good contact with the electrolyte by applying a pressure of more than 30MPa on both sides.
3. test steps:
① tabletting: take 200 mg of electrolyte powder and pour it into the mold, with an inner diameter of 10mm, and apply 350MPa tabletting;
② measurement: use vernier caliper depth gauge to measure the thickness of electrolyte sheet in the mold;
③ assembly: apply 350MPa compression after assembly, and use steel kit to keep pressure and send for measurement;
④ Test EIS: Connect the electrochemical workstation, set the test parameters, and start the test. The AC impedance test frequency range is 1MHz ~ 1Hz, and the voltage amplitude is 10 mV.
⑤ calculation of ionic conductivity: due to soft sulfide and good contact between particles, the AC impedance curve appears as a straight line approximately inclined upward by 45 degrees without obvious grain boundary capacitance resistance signal. the value of the intersection of the curve and the real axis z' is taken as the total impedance to calculate the ionic conductivity.
important tips and suggestions for use:
1. operating environment: all operations must be carried out in a glove box filled with high-purity argon (o & h o <0.1 ppm). Any exposure to air can cause material decomposition, performance failure and the production of toxic gases (H₂ S).
2. Personal protection (PPE): Even when operating in the glove box, it is recommended to wear chemical-resistant gloves (such as nitrile rubber gloves). If you need to take it out, you must wear a protective mask, goggles, and anti-static test coat.
hazard statement:
1. hydrogen sulfide gas can be released when exposed to water. the gas is colorless, highly toxic, smells of rotten eggs at low concentration, tasteless at high concentration, and may ignite spontaneously.
2, fatal by swallowing, skin contact or inhalation
3, can cause severe skin burns and eye damage
4, extremely toxic to aquatic organisms
Precautions:
1, do not contact with water.
2. Operate in an inert gas glove box to prevent moisture.
3. Wear protective gloves/protective clothing/protective eye mask.
4. Clean thoroughly after operation.
5. Do not eat, drink or smoke when using this product.
6, do not inhale dust/smoke/gas/smoke/vapor/spray.
7, avoid release into the environment.