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Newmowa NP-BX1: Three Years Later
A pair of the 2022 batch of Newmowa NP-BX1 lithium batteries for the Sony AS-30V helmet camera no longer survive a typical hour-long bike ride:

NP-BX1 – Newmowa 2022 in 2025-06 The best four have a capacity down 14% from the good old days and the weakest pair are down 29%.
The camera uses 1.9 W, so a battery with 2.5 W·hr capacity should last 78 minutes, but about 400 mV of voltage depression causes the camera to give up before using its full capacity.
So they have a useful lifetime of maybe two years in our regular bike riding schedule and I should have bought replacements last year. I hope the next batch isn’t New Old Stock or recycled cells.