Pankaj Vohra Arora

US Patent:

7112389, Sep 26, 2006

Filed:

Sep 30, 2005

Appl. No.:

11/240749

Inventors:

Pankaj Arora - Chesterfield VA, US
Simon Frisk - Richmond VA, US
Lu Zhang - Midlothian VA, US

Assignee:

E. I. du Pont de Nemours and Company - Wilmington DE

International Classification:

H01M 4/26
H01G 9/00

US Classification:

429128, 429120, 429142, 429176, 429248, 429249, 361502, 361504, 361508, 361512

Abstract:

Alkaline and lithium batteries are disclosed that advantageously include separators comprising at least one porous layer of fine fibers having a diameter of between about 50 nm and about 3000 nm that provide improved combinations of reduced thickness, dendritic barrier against short-circuiting and low ionic resistance as compared with known battery separators.

US Patent:

7170739, Jan 30, 2007

Filed:

Sep 30, 2005

Appl. No.:

11/240738

Inventors:

Pankaj Arora - Chesterfield VA, US
Simon Frisk - Richmond VA, US
Lu Zhang - Midlothian VA, US

Assignee:

E.I. du Pont de Nemours and Company - Wilmington DE

International Classification:

H01G 9/00

US Classification:

361502, 361504, 361508, 361512, 361523, 361528, 429247, 429249

Abstract:

Electrochemical double layer capacitors are disclosed that advantageously include separators having at least one porous layer of nanofibers having average diameters of between about 50 nm and about 1000 nm that provide improved combinations of reduced thickness, barrier against the development of soft short-circuits and low ionic resistance as compared with known capacitor separators.

US Patent:

7760486, Jul 20, 2010

Filed:

Aug 28, 2007

Appl. No.:

11/895912

Inventors:

Pankaj Arora - Chesterfield VA, US
Simon Frisk - Richmond VA, US

Assignee:

E. I. du Pont de Nemours and Company - Wilmington DE

International Classification:

H01G 9/02

US Classification:

361512

Abstract:

The present invention provides an aluminum electrolytic capacitor having a cathode, an anode and an improved spacer comprised of polymeric nanofibers. The nanofiber spacer offers low ionic resistance, desirable barrier properties and high electrolyte absorption. The use of the improved spacer results in devices having higher capacitance, lower ESR, less heat generation and improved capacitor manufacturing efficiency.

US Patent:

7790320, Sep 7, 2010

Filed:

Jan 2, 2007

Appl. No.:

11/619002

Inventors:

Pankaj Arora - Charlotte NC, US
Ronald W. Call - Rock Hill SC, US
Tien Dao - Charlotte NC, US
Khuy V. Nguyen - Charlotte NC, US
Donald K. Simmons - Charlotte NC, US
Zhengming Zhang - Charlotte NC, US

Assignee:

Celgard LLC - Charlotte NC

International Classification:

H01M 2/16
H01M 2/14

US Classification:

429247, 429129, 429248, 429249, 429251

Abstract:

A battery separator is a microporous membrane. The membrane has a major volume of a thermoplastic polymer and a minor volume of an inert particulate filler. The filler is dispersed throughout the polymer. The membrane exhibits a maximum Z-direction compression of 95% of the original membrane thickness. Alternatively, the battery separator is a microporous membrane having a TMA compression curve with a first substantially horizontal slope between ambient temperature and 125 C. , a second substantially horizontal slope at greater than 225 C. The curve of the first slope has a lower % compression than the curve of the second slope. The curve of the second slope is not less than 5% compression. The TMA compression curve is graphed so that the Y-axis represents % compression from original thickness and the X-axis represents temperature.

US Patent:

8557444, Oct 15, 2013

Filed:

Oct 7, 2010

Appl. No.:

12/899801

Inventors:

Pankaj Arora - Chesterfield VA, US
Stephane Francois Bazzana - Wilmington DE, US
T. Joseph Dennes - Parkesburg PA, US
Eric P. Holowka - Philadelphia PA, US
Lakshmi Krishnamurthy - Wilmington DE, US
Stephen Mazur - Wilmington DE, US
Glen E. Simmonds - Avondale PA, US

Assignee:

E I du Pont de Nemours and Company - Wilmington DE

International Classification:

H01M 2/16
H01M 4/131
H01M 4/583
H01M 4/64

US Classification:

429249, 4292313, 4292318, 429233

Abstract:

This invention provides a multi-layer article comprising a first electrode material, a second electrode material, and a porous separator disposed between and in contact with the first and the second electrode materials, wherein the porous separator comprises a nanoweb consisting essentially of a plurality of nanofibers of a fully aromatic polyimide. Also provided is a method for preparing the multi-layer article, and an electrochemical cell employing the same. A multi-layer article comprising a polyimide nanoweb with enhanced properties is also provided.

US Patent:

20020064706, May 30, 2002

Filed:

Nov 30, 2000

Appl. No.:

09/726633

Inventors:

Zhengming Zhang - Charlotte NC, US
Pankaj Arora - Charlotte NC, US

International Classification:

H01M010/50
H01M002/02

US Classification:

429/120000, 429/176000

Abstract:

The instant invention is directed to a secondary lithium battery. The battery includes a negative electrode, a positive electrode, a separator sandwiched between the electrodes, an electrolyte impregnating the separator and being in a fluid communication with the electrodes, and a metal package adapted for containing the electrodes, the separator, and the electrolyte. One of the electrodes is in thermal contact with the package.

US Patent:

20040086782, May 6, 2004

Filed:

Nov 1, 2002

Appl. No.:

10/286544

Inventors:

Zhengming Zhang - Charlotte NC, US
Donald Simmons - Charlotte NC, US
Kevin Chambers - Fort Mill SC, US
Pankaj Arora - Charlotte NC, US

Assignee:

Celgard Inc.

International Classification:

H01M002/16

US Classification:

429/142000, 429/061000, 429/248000, 429/249000

Abstract:

A battery separator for a lithium-ion secondary battery is a microporous membrane with an adjuvant. The microporous membrane is made of a thermoplastic. The adjuvant, in an effective amount, is mixed into the separator or coated thereon. The adjuvant is a material adapted to reduce or eliminate energy concentrations around the separator. The energy concentration is sufficient to initiate a reaction of the components of the lithium ion secondary battery.

US Patent:

20040166415, Aug 26, 2004

Filed:

Feb 21, 2003

Appl. No.:

10/371461

Inventors:

Zhengming Zhang - Charlotte NC, US
Pankaj Arora - Charlotte NC, US

Assignee:

Celgard Inc.

International Classification:

H01M002/16

US Classification:

429/249000

Abstract:

A lithium ion rechargeable battery comprises: a negative electrode adapted to give up electrons during discharge, a positive electrode adapted to gain electrons during discharge, a microporous separator sandwiched between said positive electrode and said negative electrode, an organic electrolyte being contained within said separator and being in electrochemical communication with said positive electrode and said negative electrode, and an oxidative barrier interposed between said separator and said positive electrode, and thereby preventing oxidation of said separator.