Does anyone know what the official position is on battery life on AW3? I'm wondering if I should be charging my watch every morning, even when there's 60-75% battery left. I've heard that the batteries are only good for so many cycles, and if I'm charging before a complete drain, I'm cutting into the life of the battery. Is that true? Anyone know what Apple says?
What you've heard is not true for the cycling part. Charging from 80% to 100% is only 20% of a cycle. 1 Cycle is 0%-100%. So 4 25% charges is 1 cycle. You are not harming your watch at all by charging it before 0% - in fact, you're helping it significantly because it is more stress on the battery to go to 0% vs charging earlier (60%-100%).
The Apple Watch has 1000 expected charge cycles (FULL 0-100%) before reaching 80% of design capacity.
-------------------------------------------------------------------------------------------------------------------------------------
https://www.apple.com/batteries/service-and-recycling/
Apple Watch Owners
Your battery is designed to retain up to 80% of its original capacity at 1000 complete charge cycles. The one-year warranty (for Apple Watch and Apple Watch Sport) and two-year warranty (for Apple Watch Edition) include service coverage for a defective battery. If it is out of warranty, Apple offers a
battery service. Prices and terms may vary.
https://www.apple.com/batteries/why-lithium-ion/
Scroll down to bottom to see charge cycle information. --- very important.
It makes charging easier.
Charge your Apple lithium-ion battery whenever you want. There’s no need to let it discharge 100% before recharging. Apple lithium-ion batteries work in charge cycles. You complete one charge cycle when you’ve used (discharged) an amount that equals 100% of your battery’s capacity — but not necessarily all from one charge. For instance, you might use 75% of your battery’s capacity one day, then recharge it fully overnight. If you use 25% the next day, you will have discharged a total of 100%, and the two days will add up to one charge cycle. It could take several days to complete a cycle. The capacity of any type of battery will diminish after a certain amount of recharging. With lithium-ion batteries, the capacity diminishes slightly with each complete charge cycle. Apple lithium-ion batteries are designed to hold at least 80% of their original capacity for a high number of charge cycles, which varies depending on the product.
----------------------------------
Like another poster above --
http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries
Depth of discharge
Discharge cycles
(NMC / LiPO4)
Table 2: Cycle life as a function of
depth of discharge. A partial discharge reduces stress and prolongs battery life, so does a partial charge. Elevated temperature and high currents also affect cycle life.
Note: 100% DoD is a full cycle; 10% is very brief. Cycling in mid-state-of-charge would have best longevity.
100% DoD ~300 / 600
80% DoD ~400 / 900
60% DoD ~600 / 1,500
40% DoD ~1,500 / 3,000
20% DoD ~1,500 / 9,000
10% DoD ~10,000 / 15,000
So if you have 10% depth of discharge (100% to 90%) --- you could do 15,000 10% cycles vs just 600 100% cycles.
Notice how doing 75% - 65% results in the least amount of stress even after 8,000 cycles!
My wife and I charge our watches frequently - whenever we can. I got a Nomad Pod so we can charge our watches away from a wall plug.
