<div dir="ltr">Bill,<div> I have had some good luck recharging frozen cells but sometimes it takes a long time to get the cells to thaw and not much charging happens until they become liquid. If there is a way to get the batteries into a heated space for awhile, or you luck out and have some warm weather, then the process can be expedited. Most of my experience is at a remote transmitter site that was underpowered with solar and had a failing generator. I would hike up there, start the backup gasoline generator and let it run a tank of gas. Eventually, the batteries would return to service though they were already mostly worn out and there was no way to determine what percentage of the low capacity was due to age, abuse or the freezing. I was surprised we didn't have more cracks (only one out of 12 had any leakage issues. I would guess these batteries (Interstate L16s') went through at least 10 or more freezing events as they had frozen cells almost every time I checked them that year. Since then, we tripled the solar (now 4kw, replaced the batteries with 16 Interstate L16's, and put in a new Generac EcoGen 6kw and the site has run flawlessly for almost a year with only a few maintenance visits to check the electrolyte levels and oil level in the generator. We have been collecting data with the OutBack OpticsRE monitoring system and after a year of literally going up there every other day to keep the site up, I enjoy taking a look at the graphs every morning and saying to myself, that's the way a system should work. </div><div><br></div><div>John Blittersdorf</div><div>Central Vermont Solar & Wind.</div></div><div class="gmail_extra"><br><div class="gmail_quote">On Thu, Dec 3, 2015 at 9:00 AM, Feather River Solar Electric <span dir="ltr"><<a href="mailto:info@frenergy.net" target="_blank">info@frenergy.net</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div bgcolor="#FFFFFF" text="#000000">
Hey Folks,<br>
<br>
I came across an off-gridder yesterday whom was getting zero
support from the dealer he had purchased his small system from, self
installed, batteries in a lightly insulated box outside. When I
inspected the electrolyte levels I discovered it was frozen in some
cells, the voltage of the 48 volt pack was ~8 volts, I didn't check
individual batteries due to these facts...I'd seen "enough".
Recently temps have been in the high teens, though we are back up to
low 30's.<br>
<br>
He does not have a genny or battery charger! I have a DC
genny which I could use to charge these batteries but should I waste
my time and his money trying to save them? Others' experience with
this situation?<br>
<br>
TIA,<br>
<br>
Bill<br>
<img alt="" src="cid:part1.08010806.07030708@frenergy.net" height="103" width="306"><span class="HOEnZb"><font color="#888888"><br>
<pre cols="72">--
Feather River Solar Electric
Bill Battagin, Owner
4291 Nelson St.
Taylorsville, CA 95983
<a href="tel:530.284.7849" value="+15302847849" target="_blank">530.284.7849</a>
CA Lic 874049
<a href="http://www.frenergy.net" target="_blank">www.frenergy.net</a>
</pre>
</font></span></div>
<br>_______________________________________________<br>
List sponsored by Redwood Alliance<br>
<br>
List Address: <a href="mailto:RE-wrenches@lists.re-wrenches.org">RE-wrenches@lists.re-wrenches.org</a><br>
<br>
Change listserver email address & settings:<br>
<a href="http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org" rel="noreferrer" target="_blank">http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org</a><br>
<br>
List-Archive: <a href="http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html" rel="noreferrer" target="_blank">http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html</a><br>
<br>
List rules & etiquette:<br>
<a href="http://www.re-wrenches.org/etiquette.htm" rel="noreferrer" target="_blank">www.re-wrenches.org/etiquette.htm</a><br>
<br>
Check out or update participant bios:<br>
<a href="http://www.members.re-wrenches.org" rel="noreferrer" target="_blank">www.members.re-wrenches.org</a><br>
<br>
<br></blockquote></div><br></div>