<div dir="ltr"><div class="gmail_default" style="font-family:arial,helvetica,sans-serif">Yeah, it's my understanding that the BMS systems on each parallel battery deals with/prevents any imbalance.</div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif"><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif">As for 48V, I have been working with some that are 51V nominal and I know there are some 60V solutions out there, so it's not so cut and dry to use amp-hours. That's why I like talk in kWh to standardize.</div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif"><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif">I am taking the DoD into account when discussing my needs. I would probably need a battery almost double the size in a lead acid chemistry!</div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif"><br></div><div><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><table border="0" cellpadding="0" cellspacing="0" style="font-family:"helvetica neue",helvetica,arial,sans-serif"><tbody><tr><td rowspan="2"></td><td rowspan="2"><table border="0" cellpadding="0" cellspacing="0" style="border-left-width:1px;border-left-style:solid;border-left-color:rgb(237,237,237);color:rgb(85,85,85);font-size:13px;padding-left:10px"><tbody></tbody></table></td></tr></tbody></table><b><div style="text-align:center"><br></div></b></div></div></div></div></div></div></div></div></div><br></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Tue, Jul 23, 2019 at 8:59 PM Jerry Shafer <<a href="mailto:jerrysgarage01@gmail.com">jerrysgarage01@gmail.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-style:solid;border-left-color:rgb(204,204,204);padding-left:1ex"><div dir="auto">William<div dir="auto">I have a few blue ion installs that was used for testing. I used eguage to monitor all DC in and out of each stack of 16k with no issues. The BMU manages everything and can be chained to each other to reduce or even prevent that issue. I have seen Blue Ions original stacks greater then 100k with years in the field, so with that cross bleed should be not a problem.</div><div dir="auto">Jerry</div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Tue, Jul 23, 2019, 4:59 PM William Miller <<a href="mailto:william@millersolar.com" target="_blank">william@millersolar.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-style:solid;border-left-color:rgb(204,204,204);padding-left:1ex"><div lang="EN-US"><div class="gmail-m_-2881034323997076791m_-2162786825219224873WordSection1"><p class="MsoNormal"><span style="font-family:Verdana,sans-serif;color:rgb(31,73,125)">Friends:</span></p><p class="MsoNormal"><span style="font-family:Verdana,sans-serif;color:rgb(31,73,125)"> </span></p><p class="MsoNormal"><span style="font-family:Verdana,sans-serif;color:rgb(31,73,125)">I am a complete newbie to any lithium technologies, so please forgive some newbie questions:</span></p><p class="MsoNormal"><span style="font-family:Verdana,sans-serif;color:rgb(31,73,125)"> </span></p><p class="MsoNormal"><span style="font-family:Verdana,sans-serif;color:rgb(31,73,125)">I am used to working in amp hours. If we are looking for a battery bank in the range of 100 kWh, this converts to about 2,083 amp/hours at 48 VDC. Is my arithmetic correct? An on-line calculator seems to confirm this.</span></p><p class="MsoNormal"><span style="font-family:Verdana,sans-serif;color:rgb(31,73,125)"> </span></p><p class="MsoNormal"><span style="font-family:Verdana,sans-serif;color:rgb(31,73,125)">The biggest Blue Ion 2 battery is 16 kwh. At 48 VDC this is about 333 amp/hours. This is like an L16. To get 100 kwh you would need to parallel 6 strings of the 16 kWh batteries. I would never do this with L-16s. Is anyone worried about circulating currents in this type of installation? Is there technology to prevent one string from cannibalizing another?</span></p><p class="MsoNormal"><span style="font-family:Verdana,sans-serif;color:rgb(31,73,125)"> </span></p><p class="MsoNormal"><span style="font-family:Verdana,sans-serif;color:rgb(31,73,125)">Here is another, more academic question below:</span></p><p class="MsoNormal"><span style="font-family:Verdana,sans-serif;color:rgb(31,73,125)"> </span></p><p class="MsoNormal"><span style="font-family:Verdana,sans-serif;color:rgb(31,73,125)">In case I am using a term I made up (which is often the case), I define circulating currents as currents flowing between parallel strings without any outside influence. For example, if you disconnected all charging and loads from an array with two parallel strings, unless the strings were absolutely identical in electrical characteristics, there would be some current flowing between the two strings. In my opinion this is the Achilles heel in parallel strings. Also my opinions: 2. The more strings you have the more chance there will be debilitating circulating currents. 3. The older the batteries, the more the electrical characteristics will vary and the more likely you will get higher circulating currents.</span></p><p class="MsoNormal"><span style="font-family:Verdana,sans-serif;color:rgb(31,73,125)"> </span></p><p class="MsoNormal"><span style="font-family:Verdana,sans-serif;color:rgb(31,73,125)">It is my theory that if you can measure the circulating currents, or the difference between parallel battery strings at any point in the operation of same, you can get a read on the health of the strings. The more the operating or idle currents diverge, the more one string will discharge the other string. I guess this is some part of a battery management system. I am guessing for the Blue Ion 2 to work in 6 parallel strings, they need to monitor and control this difference in currents.</span></p><p class="MsoNormal"><span style="font-family:Verdana,sans-serif;color:rgb(31,73,125)"> </span></p><p class="MsoNormal"><span style="font-family:Verdana,sans-serif;color:rgb(31,73,125)">We just installed a flooded battery array (2 strings of 4 Deka M6100-33 batteries). My plan is to retrofit the installation with a 1000A/100mv shunt in the negative leads of both strings. With a DVM I can spot check the circulating currents to learn about the battery health. In fact I have a <a href="https://millersolar.com/MillerSolar/Portfolio/Commercial/Cal_Trans/Remote/Remote_Control.html" rel="noreferrer" target="_blank">remote monitoring system</a> with some spare ports that can log these values. Might be an interesting experiment.</span></p><p class="MsoNormal"><span style="font-family:Verdana,sans-serif;color:rgb(31,73,125)"> </span></p><p class="MsoNormal"><span style="font-family:Verdana,sans-serif;color:rgb(31,73,125)">I appreciate any input on the viability of the Blue Ion 2 or other small battery systems in multi-string installations. My customers are asking for new technology, but I instinctively avoid parallel battery strings.</span></p><p class="MsoNormal"><span style="font-family:Verdana,sans-serif;color:rgb(31,73,125)"> </span></p><p class="MsoNormal"><span style="font-family:Verdana,sans-serif;color:rgb(31,73,125)">William Miller</span></p><p class="MsoNormal"><span style="font-family:Verdana,sans-serif;color:rgb(31,73,125)"> </span></p><p class="MsoNormal"><span style="font-family:Verdana,sans-serif;color:rgb(31,73,125)"> </span></p><p class="MsoNormal"><span style="font-family:Verdana,sans-serif;color:rgb(31,73,125)"> </span></p><p class="MsoNormal"><span style="font-family:Arial,sans-serif;color:rgb(31,73,125)">Miller Solar</span></p><p class="MsoNormal"><span style="font-family:Arial,sans-serif;color:rgb(31,73,125)">17395 Oak Road, Atascadero, CA 93422</span></p><p class="MsoNormal"><span style="font-family:Arial,sans-serif;color:rgb(31,73,125)">805-438-5600</span></p><p class="MsoNormal"><span style="font-family:Arial,sans-serif;color:rgb(31,73,125)"><a href="http://www.millersolar.com/" rel="noreferrer" target="_blank"><span style="color:blue">www.millersolar.com</span></a></span></p><p class="MsoNormal"><span style="font-family:Arial,sans-serif;color:rgb(31,73,125)">CA Lic. 773985</span></p><p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)"> </span></p><p class="MsoNormal"><span style="font-size:8pt;font-family:Arial,sans-serif;color:rgb(31,73,125)">Quote of the month: \u201cAs they age, batteries transition from energy </span></p><p class="MsoNormal"><span style="font-size:8pt;font-family:Arial,sans-serif;color:rgb(31,73,125)">storage devices to energy consuming devices.\u201c W. Miller</span></p><p class="MsoNormal"><span style="font-family:Verdana,sans-serif;color:rgb(31,73,125)"> </span></p><p class="MsoNormal"><b><span style="font-size:10pt;font-family:Tahoma,sans-serif">From:</span></b><span style="font-size:10pt;font-family:Tahoma,sans-serif"> RE-wrenches [mailto:<a href="mailto:re-wrenches-bounces@lists.re-wrenches.org" rel="noreferrer" target="_blank">re-wrenches-bounces@lists.re-wrenches.org</a>] <b>On Behalf Of </b>Lou Russo<br><b>Sent:</b> Saturday, July 20, 2019 1:50 PM<br><b>To:</b> RE-wrenches<br><b>Subject:</b> Re: [RE-wrenches] Large Off-Grid Residential System</span></p><p class="MsoNormal"> </p><div><p class="MsoNormal">Blue Ion 2.0 with Outback or SMA. Works every time. </p><div><p class="MsoNormal">Blue Planet's tech support is great, the warranty is even better. </p></div><div><div><div><div><div><div><div><p class="MsoNormal"> </p></div><div><p class="MsoNormal">Aloha,</p><div><p class="MsoNormal"> </p></div><div><p class="MsoNormal">Lou Russo</p></div><div><p class="MsoNormal"><a href="mailto:lou@spreesolarsystems.com" rel="noreferrer" target="_blank">lou@spreesolarsystems.com</a></p></div><div><p class="MsoNormal">808 345 6762</p></div><div><p class="MsoNormal">Spree Solar Systems LLC </p></div><div><p class="MsoNormal">CT-34322</p></div><div><p class="MsoNormal"> </p></div></div></div></div></div></div></div><p class="MsoNormal"> </p></div></div><p class="MsoNormal"> </p><div><div><p class="MsoNormal">On Sat, Jul 20, 2019 at 10:36 AM Jay <<a href="mailto:jay.peltz@gmail.com" rel="noreferrer" target="_blank">jay.peltz@gmail.com</a>> wrote:</p></div><blockquote style="border-style:none none none solid;border-left-width:1pt;border-left-color:rgb(204,204,204);padding:0in 0in 0in 6pt;margin-left:4.8pt;margin-right:0in"><div><div><p class="MsoNormal">Hi Marco,</p></div><div><p class="MsoNormal"> </p></div><div><p class="MsoNormal">Is the max surge 7kw, which is what is listed on line?</p></div><div><p class="MsoNormal"> </p></div><div><p class="MsoNormal">Jay</p></div><div><p class="MsoNormal">Peltz Power</p></div><div><p class="MsoNormal" style="margin-bottom:12pt"><br>On Jul 19, 2019, at 3:10 PM, Marco Mangelsdorf <<a href="mailto:marco@pvthawaii.com" rel="noreferrer" target="_blank">marco@pvthawaii.com</a>> wrote:</p></div><blockquote style="margin-top:5pt;margin-bottom:5pt"><div><p class="MsoNormal">Seven to eight Tesla Powerwalls will get you that assuming that the service entrance is no bigger than 200A.</p><div><p class="MsoNormal"> </p></div><div><p class="MsoNormal">marco <br><br>On Friday, July 19, 2019, Jason Szumlanski <<a href="mailto:jason@floridasolardesigngroup.com" rel="noreferrer" target="_blank">jason@floridasolardesigngroup.com</a>> wrote:</p><div><div><p class="MsoNormal"><span style="font-family:Arial,sans-serif">What are current popular options for battery based systems in the 100kWh range? Preferably Lithium.</span></p></div><div><p class="MsoNormal"><span style="font-family:Arial,sans-serif"> </span></p></div><div><p class="MsoNormal"><span style="font-family:Arial,sans-serif">Also, what inverter pairing is suggested with total stacked capacity of 36kW, 120/240V?</span></p></div><div><p class="MsoNormal"><span style="font-family:Arial,sans-serif"> </span></p></div><div><p class="MsoNormal"><span style="font-family:Arial,sans-serif">This is slightly larger than some of the systems I have worked with recently. I'm a bit out of the loop, particularly on the battery side of things.</span></p></div><div><p class="MsoNormal"><span style="font-family:Arial,sans-serif"> </span></p></div><div><p class="MsoNormal"><span style="font-family:Arial,sans-serif">Jason Szumlanski</span></p></div><div><p class="MsoNormal"><span style="font-family:Arial,sans-serif">Florida Solar Design Group</span></p></div><div><div><div><div><div><div><div><div><div><p class="MsoNormal" align="center" style="text-align:center"><b> </b></p></div></div></div></div></div></div></div></div></div></div></div></div></blockquote><blockquote style="margin-top:5pt;margin-bottom:5pt"><div><p class="MsoNormal" style="margin-bottom:12pt">_______________________________________________<br>List sponsored by Redwood Alliance<br><br>List Address: <a href="mailto:RE-wrenches@lists.re-wrenches.org" rel="noreferrer" target="_blank">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></p></div></blockquote></div><p class="MsoNormal" style="margin-bottom:12pt">_______________________________________________<br>List sponsored by Redwood Alliance<br><br>List Address: <a href="mailto:RE-wrenches@lists.re-wrenches.org" rel="noreferrer" target="_blank">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></p></blockquote></div></div></div>
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