PD or Iota for my upgrade?

DryCamper11 wrote:
Once the battery voltage has risen sufficiently the charger voltage limit will stop any further voltage rise by the charger. The charger current output will begin to taper. The battery will remain at roughly constant voltage. This is the absorption stage (constant voltage), as contrasted with the bulk charge mode, which was constant current. Tojan recommends that the charger limit voltage to hold no more than C/5 current (literature says no more than about C/8) in constant current bulk charge mode until 90% SOC then shift to constant voltage at 14.8 volts in the absorption stage until current drops to about about 1-3% of C-20. Then they recommend going to 13.5 float. It's hard to get comparable recommendations for Sam's Club batteries by Johnson Controls.

In both the Bulk (constant current) and Absorption (constant voltage) stages there is a benefit to shifting to above 14.4 volts.

You've pretty well got it. C/5 is a good target for quick charge vs. battery longevity. However, many on here, including BFL13, myself and... again... many others have done countless charges at C/3 or even higher without much, if any, ill effect. BFL can give you more on this. Over their lives, batteries are relatively cheap. We're talking pennies per camping day. Generator noise, to me, BFL and others is much more "expensive" wrt our camping enjoyment.

Also... the charge rate will only be C/3 for so long, i.e. in bulk. Once absorption occurs, current will, as you've learned, begin to quickly taper.

WRT Peukert, you are technically correct and good for you for clearly doing plenty of research. However...

http://www.smartgauge.co.uk/peukert_chg.html
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