New 2 stage PD lithium Converter charger yet?

StirCrazy wrote:

otrfun wrote:
Good question. Depends on what you want from your lifepo4. Maximum usability? Maximum cycle life? Or, something in the middle?
14.6v nets you maximum ah's and minimal charge times at the expense of cycle life.
You can charge a 12v lifepo4 with any voltage between say, ~13.15v and 14.6v with varying degrees of usability and cycle life. 14.6v nets you maximum ah's and minimal charge times at the expense of cycle life. ~13.15v nets you maximum cycle life with reduced ah availability and increased charge times.

There is no one charge profile that provides both max usability and max cycle life. It's either one or the other, or a little of both.

Pick your poison.

Im not sure the way this part is worded is the best. and it could be leading to a lot of the confusion.

I think it would be better to say "advertised cycle life" instead of "at the expence of cycle life" some one like BF13 or PT might interpret that as by charging to 14.6V we are only going to get 1800 cycles now.

the max figures are what the cycles are based off so 14.6 charge 100 to 0 discharge, but yes like you say if you don't need all of your battery bank operating between say 80 and 20% would normaly take a 3000 cycle battery up to the 5000 cycle range and using less than 50% so 30 to 80 could take you up to 7000 cycles. so there is a big trade off, but generaly to get more life you have to spend more on batteries to let you use that smaller amount of capacity.

Im trying to figure out how to set up my peramiters on my solar charger to stop charging at 90% right now, but I have 10x my daily use capacity so using 90% as my celing should gain me a tone of life that I probably won't live long enough to see anyways haha

I stand by my comment: "14.6v nets you maximum ah's and minimal charge times at the expense of cycle life". I'm not claiming it's a large, or a small amount, I'm simply claiming that there is a drop in cycle life, which is a true and correct statement.

I purposely worded it this way because the amount of cycle drop cannot be quantified unless you're comparing cycle life at 14.6v vs. cycle life at a specific, lower charge voltage, which I did not do.

If BFL13 or PT (or anyone else) want to assume I meant a large, small, or specific drop in cycle life, that's their right to do so. However, I only claimed there was a drop---nothing more, nothing less.

On the flipside, I very much agree with your comment, " . . . using 90% as my celing should gain me a tone of life that I probably won't live long enough to see anyways haha". Most of this debate about the best charge profile, voltage, converter, or charger for a lifepo4 is probably a moot point for the vast majority of lifepo4 users. Even the use of a single-stage 14.6v lithium converter/charger, which is probably the worst charging device you can use to charge a lifepo4, will probably still net the average lifepo4 owner 10 years of use before capacity drops below 80%.