Lithium/fluorinated carbon battery with no voltage delay

• US 4,681,823 A
• Filed: 05/19/1986
• Issued: 07/21/1987
• Est. Priority Date: 05/19/1986
• Status: Expired due to Fees

• Current Assignee: Allied Corp. (Honeywell International Inc.)
• Original Assignee: Allied Corp. (Honeywell International Inc.)
• Inventors: McCurry, Lynn E., Lockyer, George D., Tung, Hsueh S., Eibeck, Richard E., Sukornick, Bernard, Friedland, David J.
• Primary Examiner(s): Walton, Donald L.
• Application Number:
  US06/864,242
• Time in Patent Office: 428 Days
• Field of Search: 429/194, 429/197, 429/218, 252/182.1, 570/150
• US Class Current: 429/231.7
• CPC Class Codes: C01B 32/10 Carbon fluorides, e.g. [CF]nor [C2F]n graphite intercalation thereof C01B32/22
• CPC Class Codes: H01M 4/5835 Comprising fluorine or fluoride salts
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A process is disclosed for producing fluorinated carbon (CF_x) admixed which can be used in a lithium battery to eliminate low voltage at the beginning of discharge. The process uses a thick carbon bed to assure proper degree and type of underfluorination of the CF_x. The inhomogeneous fluorinated carbon produced is a fully, or overfluorinated CF_x with a small amount of underfluorinated material to eliminate voltage suppression in Li/CF_x batteries.

Claims

1. A method for producing an improved fluorinated carbon, for use as a cathode active material in a lithium fluorinated carbon battery, which inhibits initial voltage delay upon discharge, which comprises:

(a) introducing a comminuted carbon into a static bed reactor;

(b) foring a bed of said carbon to a depth of at least 0.5 cm; and

(c) subjecting said carbon bed to a fluorination reaction under controlled reaction time with fluorine to produce an inhomogeneous fluorinated carbon product and until the carbon attains a weight gain of at least 10 percent.

2. The method of claim 1 wherein the fluorination in step (c) is maintained until the carbon attains a weight gain of from about 100 to about 140 percent.

3. The method of claim 1 in which the carbon employed is selected from amorphous or crystalline carbon.

4. The method of either claim 1 or claim 3 wherein the carbon comprises a petroleum coke.

5. The method of any of claim 1 through 3 in which the carbon has a median particle size less than 30 microns.

6. The method of claim 1 wherein the fluorination is conducted at a teperature between 320-600°

C.

7. The method of claim 1 wherein the fluorinated product is washed with ethanol.

8. A Li/CF_x battery comprising the reaction product produced by the method of claim 6 in admixture with a fluorinated carbon having a different initial discharge characteristic.

9. A Li/CF_x battery comprising the reaction product produced by the method of claim 7 in admixture with a fluorinated carbon having a different initial discharge characteristic.