United States Nuclear Regulatory Commission - Protecting People and the Environment

Morning Report for September 9, 1999

                       Headquarters Daily Report

                         SEPTEMBER 09, 1999

                    REPORT             NEGATIVE            NO INPUT
                    ATTACHED           INPUT RECEIVED      RECEIVED

REGION I                               X
REGION II                              X
REGION III                             X
REGION IV                              X

Licensee/Facility:                     Notification:

Part 21 Database                       MR Number: H-99-0082
C&D Technologies                       Date: 09/09/99

Subject: Part 21 - Safety Related Battery Cell Degradation at Cooper


VENDOR: C&D Technologies                PT21 FILE NO: 99-37-0


SOURCE DOCUMENT: EN 36073               REVIEWER: REXB, C. Petrone

Preliminary information on the cell degradation was provided in morning
report H-99-0071 dated August 12, 1999. This morning report is being
revised based on information provided in a Part 21 report from C&D
Technologies dated August 25, 1999, and through discussions with vendor

The licensee for the Cooper Nuclear Station has found degradation in
several cells in their safety related batteries. The cells were
manufactured as commercial grade and subsequently dedicated as safety
related components by C&D Power Systems. The initial indication of a
problem was a lower than expected voltage on several cells during
surveillance testing. An inspection of these cells revealed excessive
growth of the positive plates. The growth was such that the positive
plates appeared to have made contact with the negative plate support
structure at the top of the cells. Abnormal growth was subsequently found
in the positive plates of other battery cells.

Analysis of the cells by C&D indicated that the positive grid material
contained excessive levels of calcium. C&D stated that the high calcium
content in the alloy would cause higher than expected growth within the
positive grids which, over time, would lead to loss of contact between
grid and the positive active material of the plate and lead to reduced
capacity, reduced voltage and shedding of material. The first sign of the
defect is visible growth within the positive plate. C&D believes that
these nonconforming levels were caused by inadequate process controls
which were corrected by new quality standards which were implemented in
January 1997. The cells are now manufactured as safety grade under 10 CFR
50, Appendix B, rather than being manufactured as commercial grade and
later being dedicated for safety applications.

The defective cells were all type LCR-25 manufactured from 1995 to 1997
under five specific work order numbers, all of which were installed at
Cooper. C&D believes that no other utility had received nonconforming
cells. However, they are continuing their review and plan to submit a
final evaluation to the NRC and any affected utilities within 30 days.

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