In most of my use cases there is no "enough", daily cycling or dozens per month anyway, usually just replace at EoL defined as 70-75% SoH, so longer the betterPajda wrote: If you insist on longer cycle life (500 full cycles should be enough for most applications)
So which batteries do you recommend for the below in LI chemistries, not counting LTO or LFP?
Cost per Ah **per year** is the Most Important factor
Must be readily available, consistent supply
Next is per-cell Ah capacity, higher is better, building and maintaining large banks, so fewer cells is a huge advantage
power density is irrelevant, bank sized to keep discharge rates below 0.2C most of the time, never over 0.5C
charging usually at 0.2C, sometimes 0.5C when fast is required
It seems you don't test for usage patterns other than 100% DoD, but just FYI
LVC is 3.2V (low current remember), and
charge termination is CC-only, end V set so SoC is kept well under 95% of that reached by stopping at 4.1V at 0.3C
In effect translates to keeping cycling between about 10% & 90% of the SoC defined by maker specs,
but only where range is critical, otherwise I try to stop discharge at between 50-70% DoD
or faster charging like 0.5C then take only LGs. Sanyo GA suffers with steep initial capacity loss and the most important problem is its huge DCIR rise. VC7 is very expensive and inferior to both LGs.
in best price category: Samsung 29E, Panasonic PF, LG M29, Sony NC1 I would recommend 29E as the best chioce. Panasonic PF is slightly worse under almost all cycle life test. PF is only better in fast charging (like 0.7-1C). I do not already have data for M29 and NC1 because I started with their cycle life tests only few days ago.