"sms" wrote in message
news
On 2/6/2018 8:48 PM, Jeff Liebermann wrote:
On Tue, 6 Feb 2018 10:52:50 -0800, sms
wrote:

My wife's Lezyne Deca 1500XXL stopped taking a charge, at all. Taking it
apart, I saw that the batteries were made in July 2015. Not too good for
it to stop working that soon. These lights don't have user-replaceable
batteries, but by removing two screws I was able to open it, and the
battery pack does have a connector on it so at least they didn't solder
it directly to the printed circuit board.

I don't see a problem. If your wife used the light every day for
about 2 years, that would be 730 charge cycles. That's about the
correct lifetime for a 60% DoD (depth of discharge). See table 2:
http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries

Not nearly every day. I'd estimate about 200 total charge/discharge
cycles. Something failed in the battery pack because it wasn't like the
operating time was less than when new, the pack would not charge at all.

Memory effect is usual on nickel chemistry batteries that are regularly only
partly discharged - not so far heard of it on lithium.