That's what Optimate-lithium claims, although there is no user-accessible output on internal resistance measurements. Along with other sanity checks, it looks for dropped / shorted cells etc during the charge process and periodically stops and tests them for voltage retention and I suppose IR before issuing a pass. I liked it for the fact that it had more than just voltage smarts, but also looked at internal IR.
I have an IR checker for PB, (ac waveform type, not a load test) and I'm NOT going to use that for any IR measurements. Not sure the LiFepo4 will take kindly to that type of IR checker.
Thanks for the tips - although I have adjusted the voltages downward for Shorai's LiFepo4, instead of the higher Li/cobalt values. The Shorai charger has a convenient store mode which discharges (or brings up if need be) a pack to about 80-90 percent and then shuts off and monitors.
To simulate a typical solar charge controller sitting at 14.4v for a few hours waiting for the sun to drop, I used a gel-specific battery tender that rises to only 14.4v max, (which surprised me since I expected 14.2v max) but doesn't seem to drop to float for about 6 hours, and no short-term damage seems evident, although I'm sure that isn't good for cycle life on a daily basis. An agm-specific battery tender will rise to 14.6v and does drop to float quickly, but I see no need to hit 14.6v daily.
Either one of my Morningstar or Xantrex C12 controllers do an ok job of charging, although I'm going to look into one that just stops once they reach the target voltage. Maybe the Genasun's do that, I'll have to check.
Right now I am the one doing the charge cutoff since my stuff is portable and I keep an eye on terminal voltages. I'm really enjoying the flat charge/discharge curve, and slowly losing my obsession over obtaining 100% charge which is not really necessary. Quite convenient for solar, but it doesn't relieve one from actually planning their power-budget to do it right. And at this point with LiFepo4, that's expen$$ive.
I have an IR checker for PB, (ac waveform type, not a load test) and I'm NOT going to use that for any IR measurements. Not sure the LiFepo4 will take kindly to that type of IR checker.
Thanks for the tips - although I have adjusted the voltages downward for Shorai's LiFepo4, instead of the higher Li/cobalt values. The Shorai charger has a convenient store mode which discharges (or brings up if need be) a pack to about 80-90 percent and then shuts off and monitors.
To simulate a typical solar charge controller sitting at 14.4v for a few hours waiting for the sun to drop, I used a gel-specific battery tender that rises to only 14.4v max, (which surprised me since I expected 14.2v max) but doesn't seem to drop to float for about 6 hours, and no short-term damage seems evident, although I'm sure that isn't good for cycle life on a daily basis. An agm-specific battery tender will rise to 14.6v and does drop to float quickly, but I see no need to hit 14.6v daily.
Either one of my Morningstar or Xantrex C12 controllers do an ok job of charging, although I'm going to look into one that just stops once they reach the target voltage. Maybe the Genasun's do that, I'll have to check.
Right now I am the one doing the charge cutoff since my stuff is portable and I keep an eye on terminal voltages. I'm really enjoying the flat charge/discharge curve, and slowly losing my obsession over obtaining 100% charge which is not really necessary. Quite convenient for solar, but it doesn't relieve one from actually planning their power-budget to do it right. And at this point with LiFepo4, that's expen$$ive.
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