According to the Battery University, charging to 4.1V/cell instead of 4.2V/cell will double the cycle life of Lipo's as quoted from here:

       http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries

"Most Li-ions charge to 4.20V/cell, and every reduction in peak charge voltage of 0.10V/cell is said to double the cycle life. For example, a lithium-ion cell charged to 4.20V/cell typically delivers 300–500 cycles. If charged to only 4.10V/cell, the life can be prolonged to 600–1,000 cycles; 4.0V/cell should deliver 1,200–2,000 and 3.90V/cell should provide 2,400–4,000 cycles."

I think most chargers can be programmed to charge to a lower peak.  Of course if you start at a lower voltage you discharge deeper too - so it probably cannot be done if you are using more than 65%-70% of capacity.  However I am I am currently flying a couple airplanes for which that is not a problem.

Just curious if anyone is actually using a 4.1V charge and what your experience is?

...and THANKS in advance for sharing your experience.

Lost capacity should be easy to test: charge to 4.1 and then charge ( but don't balance) to 4.2.
The extra amount put in is what you are giving up.

But you will draw the battery a bit lower in discharge, both because you are starting off less than fully charged and because the average voltage is lower.
Energy(W-hours) flies the model through the pattern, not capacity.

How this all comes out in battery life would be interesting to know.
Best way to test this would be a single user to have two sets of batteries and run them each way for a while (a season perhaps) and compare them.

Pat MacKenzie

Yes, I charge battery just before flying, so it does not stay charged too long. and I store them discharged after flight. I cut charging at 2A so it is not fully charged anyway. I also do not balance them at every charge, I do it after aproximately 10 flights. If I see tendecy to disbalance, means battery is already bad so I simply replace. They do usually 200 to 400 flights.

After flying for a couple years with full charge batteries 4.20 charge and experiencing lots of short life  and extremely unbalanced cells batteries, Less than 50 charges   On Hobby King cheap batteries .

I have cut down the max charge to 4.14 volts  and went to a over capacity battery . With changing to a thunder-power battery , the battery voltage is 3.8 after flight , right at storage charge.

The model needed the nose weight , so extra battery capacity and lower voltage  full charge was not a issue .

No battery failures with over 100 cycles on battery 1

Might be something to not charging to 100 % and not discharging too deep.

Lesson learned , do not buy chaap batteries, they are not really cheaper and follow Igor's advice