The Smell of Molten Projects in the Morning

Ed Nisley's Blog: Shop notes, electronics, firmware, machinery, 3D printing, laser cuttery, and curiosities. Contents: 100% human thinking, 0% AI slop.

Day: September 21, 2012

  • Dead-on-arrival Lithium Cell

    DOA Energizer CR2032 cell
    DOA Energizer CR2032 cell

    The display on Mary’s Cateye Astrale cyclocomputer (remember cyclocomputers?) faded to gray, which meant a new CR2032 lithium cell was in order. I grabbed one from the heap, popped out the old cell, inserted the new cell, and … the display stayed blank.

    Quick like a bunny, I reinserted the old cell to save the odometer (15524 miles) and wheel circumference (1475 mm) data; the display returned to dim gray.

    The “new” cell, which came from an unopened pack, read 0.45 V with no load…

    The cell didn’t have a date code, but the package sports a cryptic MU that might encode the date of manufacture or the date of packaging or the copyright date or something; the various search results aren’t forthcoming and the Energizer site gives no explanation.

    I’m pretty sure I haven’t owned that package for more than a few years and it’s been in a shirtsleeve environment (plus the occasional hot van) ever since.

    Another Energizer cell from a more recent lot, bearing CA on the package and YA on the cell, worked fine.

    Being that sort of bear, I wrote the date and mileage on the previous cell (a Newsun, whoever they are, with a 3Y code), because the last time around the odometer value didn’t survive the cell change. The current total works out to 277 miles/month = 3300 miles/year, including winter downtime, which is fine with us; we mostly ride the bikes around town on errands and take the occasional tour.