<div dir="ltr"><div>Thanks for the AGM equalization info, all. My horror stories have all been with VRLAs. I will start trying the short EQ in the future after seeing the explanations.....not enough time to start releasing moisture.</div><div><br></div><div>Best;</div><div><br></div><div><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><span style="font-size:12.8px">Dan Fink</span><div style="font-size:12.8px">Professor of Solar Energy Technology, Ecotech Institute</div><div style="font-size:12.8px">IREC Certified Instructor\u2122 for: </div><div style="font-size:12.8px">~ PV Installation Professional</div><div style="font-size:12.8px">~ Small Wind Installer</div><div style="font-size:12.8px">Executive Director, Buckville Energy</div><div style="font-size:12.8px">NABCEP Registered Continuing Education Providers\u2122</div><div style="font-size:12.8px">NABCEP PV Associate</div><div style="font-size:12.8px"><br><a value="+19706724342" style="color:rgb(17,85,204)">970.672.4342</a></div><br> </div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div><br><br><div class="gmail_quote"><div dir="ltr">On Fri, Nov 23, 2018 at 11:34 AM Starlight Solar Power Systems <<a href="mailto:larry@starlightsolar.com">larry@starlightsolar.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div style="word-wrap:break-word">Dan, Jay,\u2026<div><br><div>I\u2019m a huge fan of equalizing AGM batteries often. Some mfg. forbid it; some recommend it for corrective procedure for lost capacity. From 16 years of simple observation and thousands of battery systems installed, customers that equalize AGM\u2019s are getting much longer battery life compared to charging to Mfg. specs. only. </div><div><br></div><div>A short EQ of 30 minutes after absorption is complete seems to be key. If the battery is healthy, current is extremely low at the end of Absorb. Applying 2.6 Vpc, the current rises for a short time then drops back very low. There is not enough current or time to create heat or pressure to release moisture. </div><div><br></div><div>The EQ cycle we recommend is every 10 days or less frequently. One customer that equalizes <u>daily</u> is at 13 years on a set of Lifeline (Concorde) GPL-4CT batteries. Others are at 10-12 years. Customers that do not EQ seem to get 4-6 years. </div><div><br></div><div>This is all anecdotal but having some understanding what is happening in the electrochemical process makes me a believer. Through charging and discharging, some less active areas of the plates retain unconverted lead sulphate after normal charging. These areas of sulfate continue to grow in hardness and size with each cycle and eventually form a layer with strong bonds that can't be removed through normal charging. Once this process starts (perhaps within 30 days!), these bonds continue to increase. My belief is that by applying a temporary high voltage after most PbSO4 has been recombined, these areas are targeted for recombination. Slowing the growth of irreversible sulfation results in retaining higher capacity and thus longer cycle life. Just my opinion developed over the years it took me to acquire a gray beard. </div><div><div><div style="color:rgb(0,0,0);font-family:Helvetica;font-size:14px;font-style:normal;font-variant:normal;font-weight:normal;letter-spacing:normal;line-height:normal;text-align:start;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px;word-wrap:break-word"><div style="color:rgb(0,0,0);letter-spacing:normal;text-align:start;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px;word-wrap:break-word"><div style="color:rgb(0,0,0);letter-spacing:normal;text-align:start;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px;word-wrap:break-word"><br><span>Larry Crutcher</span><br><span>Starlight Solar Power Systems</span><br><br></div><br class="m_-9111629126915678830Apple-interchange-newline"></div><br class="m_-9111629126915678830Apple-interchange-newline"></div></div></div></div></div><br>
</blockquote></div></div>