In-battery polymerization of conducting polymers for high-rate charging cathodes

Patent metadata

Field	Value
Publication number	US-9831488-B1
Application number	US-201715434083-A
Country	US
Kind code	B1
Filing date	Feb 16, 2017
Priority date	Dec 11, 2016
Publication date	Nov 28, 2017
Grant date	Nov 28, 2017

Abstract

Cathodes for a fast charging lithium ion battery, processes for manufacturing thereof and corresponding batteries are provided. Cathode formulations comprise cathode material having an olivine-based structure, binder material, and monomer material selected to polymerize into a conductive polymer upon partial delithiation of the cathode material during at least a first charging cycle of a cell having a cathode made of the cathode formulation. When the cathode is used in a battery, polymerization is induced in-situ (in-cell) during first charging cycle(s) of the battery to provide a polymer matrix which is evenly dispersed throughout the cathode.

First claim

The invention claimed is:

1. A cathode, prepared from a cathode formulation comprising:
cathode material having an olivine-based structure,
binder material, and
monomer material selected to polymerize into a conductive polymer upon partial delithiation of the cathode material during at least a first charging cycle of a cell having the cathode,
wherein:
the monomer material is in monomer form in the cathode in its pristine form prior to the first charging cycle of the cell,
the partial delithiation is carried out electrochemically during the first charging cycle of the cell,
following the first charging cycle of the cell, the monomer material is at least partly polymerized,
the cathode material is A z MXO 4 wherein A is Li, alone or partially replaced by at most 10% of Na and/or K; 0≦z≦1, M is at least 50% of Fe(II) or Mn(II) or mixture thereof; and XO 4 is PO 4 , alone or partially replaced by at most 10 mol % of at least one group selected from SO 4 and SiO 4 , and
the monomer material consists of monomers of at least one of pyrrole, aniline, thiophene, phenyl mercaptan, furan, phenol, ethylenedioxythiophene and styrenesulfonate.

2. The cathode of claim 1 , wherein the cathode material comprises LFP (LiFePO 4 ).

3. The cathode formulation of claim 1 , further comprising a carbon coating.

4. The cathode of claim 1 , wherein at least one ring in the monomers is substituted with at least one of: one or more straight, branched or bridged alkyl, alkenyl, oxa-alkyl, oxa-alkenyl, aza-alkyl, aza-alkenyl, thia-alkyl, thia-alkenyl, sila-alkyl, sila-alkenyl, aryl, aryl-alkyl, alkyl-aryl, alkenyl-aryl, dialkylamino and dialkylazo compounds comprising about 1-30 carbon atoms.

5. The cathode of claim 1 , wherein the binder material consists of at least one of: carboxymethyl cellulose (CMC), polyvinylidene difluoride (PVDF), polyacrylic acid (PAA), polyethylene oxide (PEO), polyvinyl alcohol (PVA) and alginate.

6. The cathode of claim 1 , comprising 80-90% of the cathode material, 1-10% of the binder material and 1-10% of the monomer material.

7. The cathode of claim 1 , comprising 90-98% of the cathode material, 1-5% of the binder material and 1-5% of the monomer material.

8. A cell comprising the cathode of claim 1 .

9. A cell comprising:
an anode,
electrolyte,
a separator, and
a cathode comprising:
cathode material having an olivine-based structure,
binder material, and
a conductive polymer formed during at least a first charging cycle of the cell from monomer material selected to polymerize into the conductive polymer upon partial delithiation of the cathode material,
wherein:
the monomer material is in monomer form in the cathode in its pristine form prior to the first charging cycle of the cell,
the partial delithiation is carried out electrochemically during the first charging cycle of the cell,
following the first charging cycle of the cell, the monomer material is at least partly polymerized,
the cathode material is A z MXO 4 wherein A is Li, alone or partially replaced by at most 10% of Na and/or K; 0≦z≦1, M is at least 50% of Fe(II) or Mn(II) or mixture thereof; and XO 4 is PO 4 , alone or partially replaced by at most 10 mol % of at least one group selected from SO 4 and SiO 4 , and
the monomer material consists of monomers of at least one of pyrrole, aniline, thiophene, phenyl mercaptan, furan, phenol, ethylenedioxythiophene and styrenesulfonate.

10. The cell of claim 9 , having a charging curve, in at least a first charging thereof, which comprises a local peak at a specified potential which corresponds to a polymerization reaction of the monomer material in presence of the partially delithiated cathode material.

11. A method comprising configuring a cathode made of cathode material having an olivine-based structure for in-situ polymerization, by adding to the cathode material monomer material selected to polymerize into a conductive polymer upon partial delithiation of the cathode material during at least a first charging cycle of a cell with the cathode,
wherein the monomer material is in monomer form in the cathode in its pristine form prior to the first charging cycle of the cell,
the partial delithiation is carried out electrochemically during the first charging cycle of the cell,
following the first charging cycle of the cell, the monomer material is at least partly polymerized,
the cathode material is A z MXO 4 wherein A is Li, alone or partially replaced by at most 10% of Na and/or K; 0≦z≦1, M is at least 50% of Fe(II) or Mn(II) or mixture thereof; and XO 4 is PO 4 , alone or partially replaced by at most 10 mol % of at least one group selected from SO 4 and SiO 4 , and
the monomer material consists of monomers of at least one of pyrrole, aniline, thiophene, phenyl mercaptan, furan, phenol, ethylenedioxythiophene and styrenesulfonate.

12. The method of claim 11 , further comprising polymerizing the monomers during the at least first charging cycle of the cell.

13. The method of claim 11 , further comprising operating the cell at a charging and/or discharging rate of at least 5 C.

Assignees

• Storedot Ltd

Inventors

• Ophir Carmit
• Brakha Libi
• Burshtain Doron
• Aronov Daniel

Classifications

• C08G2261/18

  conjugated · CPC title

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• C08G2261/3223

  containing one or more sulfur atoms as the only heteroatom, e.g. thiophene · CPC title

• H01M4/5825 Primary

  Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines · CPC title

• H01M4/583

  Carbonaceous material, e.g. graphite-intercalation compounds or CFx · CPC title