Metal-ion deposition regulator for suppressing dendrite formation in electrochemical cells

An electrochemical cell comprising:

• an anode;
• a cathode;
• a liquid electrolyte;
• and
• a metal-ion deposition regulator containing two membranes and a plurality of two-dimensional porous nanosheets sandwiched between the two membranes,
• wherein the metal-ion deposition regulator is capable of distributing flux of metal ions passing through the metal-ion deposition regulator and regulating the deposition of the metal ions onto the cathode or anode thereby suppressing dendrite growth in the electrochemical cell.

A method of making a metal-ion deposition regulator to regulate the flux and deposition of metal ions in an electrochemical cell, the method comprising:

• dispersing graphene oxide particles into a mixture of deionized water and ethanol;
• (sonication)
• adding a silicon-containing inorganic material and quantity of a bonding agent to promote bonding between the graphene oxide particles and the silicon-containing inorganic material to form a suspension containing the graphene oxide particles, silicon-containing inorganic material, water, and the bonding agent;
• sonication
• adding ammonia solution to the suspension causing precipitation of a composite containing the graphene oxide particles, silicon-containing inorganic material and the bonding agent;
• extracting the composite by removing the ammonia solution and water;
• centrifuging the suspension containing the precipitate, water and ammonia;
• drying the composite to form a dry composite;
• heating the dry composite to a temperature range of 500-800 C for 6-24 hours resulting in the removal of the graphene oxide leaving behind porous nanosheets of silicon dioxide;
• mixing the nanosheets with a polymeric binder and an organic solvent to result in a slurry;
• coating a first membrane made of a polymer with the slurry;
• heating the first membrane coated with the slurry in at temperature range of 30-50° C. for 4-24 hours to form dried porous nanosheets attached to the first membrane made of a polymer;
• and
• sandwiching the dried porous nanosheets between the first membrane made of a polymer and a second membrane made of a polymer to be in contact with the two membranes;
• wherein the sandwich comprising the first and second membranes made of a polymer and the porous nanosheets of silicon dioxide form a metal-ion deposition regulator.