Repeating, again and again:eMark said:As a general rule it was my understanding that it's better to go with an 80% charge and 50% discharge than an 80% charge and 80% discharge? Maybe, for some an 80% charge and 65% discharge is the happy medium that best suits one's daily ebiking routine. Here's a real-life scenario that may be similar to Erik's daily ebiking routine with two possible options being 80/50 or 80/80 ...
If there are two batteries the same size and one has a lot greater mAh capacity, very likely that will have a shorter lifespan.
How "easy-going" the usage "routine" is has nothing to do with anything.
Now, if you are happy spending more money and carrying around a lot more size & weight, that will extend lifespan, to the point that $/Ah **per year** may be cheaper.
And if you don't need high real-life C-rate discharge, you can likely save money there too. But often that factor correlates with good lifespan too.
And **please** stop propagating this 80% malarkey! Treat 4.05-4.1Vpc as **100% Full** and be done with it. How long you hold Absorb is a small factor, how long you **sit** at any definition of "Full" a **much** bigger one, but none of this has anything to do with this mythical "80%" number.
And (again again) 3.0Vpc and lower is where the cell vendors would love for us to go every cycle, so when you see that, make a mental note to discount that source for longevity advice, that is more like a
very stressful "avoid approaching" minimum level, like running chinese electronics close to their advertised rating, not at all a good idea IRL.
BU is not a canonical source, OK for 101-level noob orientation maybe. . .
0% is not "a low end" and is in opposition to longevity.
A shallower DoD is **always** going to give longer lifespan, and that tradeoff is a 100% personal variable, no rule of thumb can be generalized, other than
based on **resting** voltage
regularly allowing a drop to 3.2V will be a very large sacrifice of life cycles
while 3.4V or higher will be much healthier.
How much IRL % capacity you are "sacrificing" will vary hugely by cell model & chemistry.