The OEM lithium batteries in my Nuheara IQbuds² MAX not-really-hearing-aids lasted for about 2-½ years before needing replacement. Two more years pretty well did those in and I replaced them again without fanfare about a year ago.
After replacing the 802050 pouch battery in the charging case and having discovered two spare LIR1654 batteries at the back of a workbench, I installed those and renewed the gaffer tape holding the earbuds together:
The workbench stash also disgorged the old Varta LIR1654 batteries, but not the OEM ones, so a test session seemed in order:
The Varta batteries (red and blue traces) are in sad shape, after two years of regular use and another three years idling in a small bag. The EEMB batteries (pink and cyan traces) are in better shape, despite their year of use, with the lower pair of traces showing their as-extracted charge and the upper three traces their just-charged capacity.
They’re still doing better than their 0.4 W·hr nominal capacity, which is not to be sniffed at, particularly as the tester’s minimum 150 mA current presents a rather stiff load for a 100-ish mA·hr cell.
This being a quick-n-dirty set of tests, a simple discharging “fixture” sufficed:
The charging “fixture” wasn’t much fancier:
The EEMB batteries are in the bag and may remain in good shape after two more years, ready for another tour in the earbuds when their relatives wear out.
The Smell of Molten Projects in the Morning 
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