From Cell Deviation to Customer Report: A 16S LFP Pack Review

This review follows one 16S lithium iron phosphate (LFP) pack rated at 45 Ah. The source displays “SOS” but does not define the label; no meaning or root cause is assigned here.

From first flag to safe transfer

Reviewers flagged a deviation at cell No. 12 during a routine scan on Aug 22. It worsened from Aug 23 through 26 as the displayed SOS value fell. On Aug 27, the pack was taken out of circulation, locked and transferred safely.

Capacity check and teardown

A Sep 1 recheck at 0.33C measured 33.91 Ah—75.36% of the 45 Ah rating (33.91 ÷ 45 × 100). That figure applies to this pack under this test condition; it is not a general performance benchmark.

The Sep 4 teardown inspection identified abnormalities in the end cover, wound core, electrodes and separator. A report was prepared and sent to the customer. The supplied record does not identify a cause for these findings.

Response timeline

The dates and figures below are reproduced from the supplied record.