Systems and methods for minimizing and preventing dendrite formation in electrochemical cells
Embodiments described herein relate to electrochemical cells with dendrite prevention mechanisms, and methods of producing and operating the same. In some aspects, an electrochemical cell can include an anode and a cathode material disposed on a cathode current collector, the cathode material and the cathode current collector forming a cathode. The electrochemical cell further includes a first separator disposed on the anode, a second separator disposed on the cathode, and an interlayer disposed between the first separator and the second separator, the interlayer including electroactive material, the interlayer including a source of lithium ions, the lithium ions configured to migrate toward the anode upon a voltage difference between the interlayer and the anode exceeding a threshold value. In some embodiments, the anode can include an anode material disposed on an anode current collector. In some embodiments, the anode material can include graphite, silicon, and/or hard carbon.
1 . An electrochemical cell, comprising:
an electronically conductive center tube;
an anode disposed on an anode current collector;
a cathode disposed on a cathode current collector;
a first separator having a first length, disposed on the anode;
a second separator having a second length, disposed on the cathode, the second length greater than the first length;
an interlayer disposed between the first separator and the second separator, such that the interlayer includes an exposed portion coupled to the second separator and not the first separator, the interlayer electrically coupled to the electronically conductive center tube; and
a casing containing the electronically conductive center tube, the anode, the anode current collector, the cathode, the cathode current collector, and the interlayer, the casing electrically coupled to the electronically conductive center tube.
2 . The electrochemical cell of claim 1 , wherein the anode, the anode current collector, the cathode, the cathode current collector, and the interlayer are disposed around the electronically conductive center tube.
3 . The electrochemical cell of claim 1 , wherein at least one of the anode current collector or the cathode current collector is disposed around the electronically conductive center tube with an insulative material disposed therebetween.
4 . The electrochemical cell of claim 1 , wherein the interlayer extends beyond at least one of the first separator or the second separator and folds or bends to directly contact the electronically conductive center tube.
5 . The electrochemical cell of claim 1 , wherein the interlayer is electrically coupled to the electronically conductive center tube via a piece of conductive material.
6 . The electrochemical cell of claim 1 , wherein the electronically conductive center tube directly contacts the casing.
7 . The electrochemical cell of claim 1 , wherein the interlayer includes an electronically conductive material.
8 . The electrochemical cell of claim 1 , wherein the interlayer includes at least one of activated carbon, hard carbon, soft carbon, conductive carbon particles, carbon black, graphitic carbon, carbon fibers, carbon microfibers, vapor-grown carbon fibers (VGCF), fullerenic carbons including “buckyballs”, carbon nanotubes (CNTs), multiwall carbon nanotubes (MWNTs), single wall carbon nanotubes (SWNTs), graphene, graphene sheets or aggregates of graphene sheets, and materials comprising fullerenic fragments.
9 . The electrochemical cell of claim 1 , wherein the interlayer includes at least one of LFP, NMC, LMO, or LMFP.
10 . The electrochemical cell of claim 1 , wherein the interlayer includes at least one of aluminum, platinum, or gold.
11 . The electrochemical cell of claim 1 , wherein the casing has a cylindrical shape.
12 . The electrochemical cell of claim 1 , further comprising a monitor tab electrically coupled to the interlayer.
13 . An electrochemical cell assembly, comprising:
an electrochemical cell comprising:
an anode;
a cathode;
an interlayer assembly disposed between the anode and the cathode, the interlayer assembly including:
a first separator having a first length;
a second separator having a second length less than the first length; and
an interlayer material disposed between the first separator and the second separator, such that the interlayer material includes an exposed portion coupled to the first separator and not the second separator;
a casing containing the electrochemical cell; and
an electronically conductive strip of material contacting the exposed portion of the interlayer material and the casing to electrically couple the interlayer material to the casing.
14 . The electrochemical cell assembly of claim 13 , wherein the second separator is disjointed, such that the second separator includes a first portion and a second portion, the first portion on a first side of the exposed portion of the interlayer material, the second portion on a second side of the exposed portion of the interlayer material, the second side opposite the first side.
15 . The electrochemical cell assembly of claim 13 , wherein electrochemical cell is a first electrochemical cell, the anode material is a first anode material, the cathode material is a first cathode material, the interlayer assembly is a first interlayer assembly, the interlayer material is a first interlayer material, and the electronically conductive strip of material is a first electronically conductive strip of material, the electrochemical cell assembly further comprising:
a second electrochemical cell disposed in the casing, the second electrochemical cell comprising:
a second anode;
a second cathode;
a second interlayer assembly disposed between the second anode and the second cathode, the second interlayer assembly including:
a third separator having a third length;
a fourth separator having a fourth length less than the third length; and
a second interlayer material disposed between the third separator and the fourth separator, such that the second interlayer material includes an exposed portion coupled to the third separator and not the fourth separator; and
a second electronically conductive strip of material disposed on the exposed portion of the second interlayer material, such that the second electronically conductive strip of material contacts the exposed portion of the second interlayer material and the casing.
16 . The electrochemical cell assembly of claim 15 , wherein the exposed portion of the first interlayer material is a first exposed portion, the first interlayer material including a second exposed portion, the electrochemical cell assembly further comprising:
a third electrochemical cell disposed in the casing, the third electrochemical cell comprising:
a third anode;
a third cathode;
a third interlayer assembly disposed between the third anode material and the third cathode material, the third interlayer assembly including:
a fifth separator having a third length;
a sixth separator having a fourth length less than the third length; and
a third interlayer material disposed between the fifth separator and the sixth separator, such that the third interlayer material includes an exposed portion coupled to the fifth separator and not the sixth separator; and
a third electronically conductive strip of material disposed on the exposed portion of the third interlayer material, such that the third electronically conductive strip of material contacts the exposed portion of the third interlayer material and the second exposed portion of the first interlayer material.
17 . The electrochemical cell assembly of claim 13 , wherein the electrochemical cell is formed into a spiral shape inside the casing.
18 . The electrochemical cell assembly of claim 13 , wherein the electrochemical cell is formed into a Z-fold shape inside the casing.
19 . The electrochemical cell assembly of claim 13 , wherein the electronically conductive strip of material includes at least one of a metal, aluminum, 304 stainless steel, 316 stainless steel, nickel, nickel plating.
20 . The electrochemical cell assembly of claim 13 , wherein the casing is electronically conductive.
21 . The electrochemical cell assembly of claim 13 , wherein the electronically conductive strip of material is integrated into the casing and extends from an interior wall of the casing as a projection.
22 . The electrochemical cell assembly of claim 13 , wherein the casing includes at least one of titanium, Ti64, or aluminum.