<html><head></head><body><div style="color:#000; background-color:#fff; font-family:times new roman, new york, times, serif;font-size:16px"><div id="yui_3_16_0_ym19_1_1522330818032_35631"><span><br></span></div><div id="yui_3_16_0_ym19_1_1522330818032_35631"><span id="yui_3_16_0_ym19_1_1522330818032_35639">Thanks for those details Sean.</span></div><div class="qtdSeparateBR" id="yui_3_16_0_ym19_1_1522330818032_35632"><br><br></div><div class="yahoo_quoted" id="yui_3_16_0_ym19_1_1522330818032_35636" style="display: block;"> <div style="font-family: times new roman, new york, times, serif; font-size: 16px;" id="yui_3_16_0_ym19_1_1522330818032_35635"> <div style="font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 16px;" id="yui_3_16_0_ym19_1_1522330818032_35634"> <div dir="ltr" id="yui_3_16_0_ym19_1_1522330818032_35633"> <font size="2" face="Arial" id="yui_3_16_0_ym19_1_1522330818032_35638"> <hr size="1" id="yui_3_16_0_ym19_1_1522330818032_35637"> <b><span style="font-weight:bold;">From:</span></b> Sean T. Stevenson via Personal_Submersibles <personal_submersibles@psubs.org><br> <b><span style="font-weight: bold;">To:</span></b> personal_submersibles@psubs.org <br> <b><span style="font-weight: bold;">Sent:</span></b> Wednesday, March 28, 2018 10:41 PM<br> <b><span style="font-weight: bold;">Subject:</span></b> Re: [PSUBS-MAILIST] 36vdc charger<br> </font> </div> <div class="y_msg_container" id="yui_3_16_0_ym19_1_1522330818032_35656"><br><div id="yiv4611619471"><div id="yui_3_16_0_ym19_1_1522330818032_35657">The issue with charging multiple cells in series is that small variances in internal resistance of each cell can lead to cell imbalance over time. This also happens to some extent in parallel configurations, but at least then you are controlling the charge voltage across the cell. If you have a sophisticated battery management system which can isolate or switch charge voltage to individual cells, you can significantly extend the working life of the battery, but it may be cheaper just to replace batteries more often. I might give some consideration to high current capability switches to isolate and charge cells independently in the absence of a BMS. If I were constrained to a series battery configuration, I would do all I could to eliminate any resistance between them, such as using large bus bars instead of cables.<br clear="none"><br clear="none">Sean <br clear="none"><br clear="none"><br clear="none"><br clear="none">-------- Original Message --------<br clear="none">On Mar 28, 2018, 14:12, hank pronk via Personal_Submersibles < personal_submersibles@psubs.org> wrote:<blockquote class="yiv4611619471protonmail_quote"><br clear="none"></blockquote></div><div class="yiv4611619471yqt5475228968" id="yiv4611619471yqt52782"><div><div style="font-family:Helvetica Neue, Helvetica, Arial, sans-serif;font-size:13px;"><div></div>
<div>Jon,</div><div>I had a 36V system for a season but am back to two 24V banks, but I always charge 12V at a time. It is also easier to find a charger for AGM in 12 or 24V. Sean mentioned one time to charge individual batteries instead of a group and I have followed that advice.</div><div>Hank</div><div><br clear="none"></div>
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On Wednesday, March 28, 2018, 1:38:34 PM MDT, Jon Wallace via Personal_Submersibles <personal_submersibles@psubs.org> wrote:
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<div><div id="yiv4611619471"><div><div style="color:#000;background-color:#fff;font-family:times new roman, new york, times, serif;font-size:16px;"><div id="yiv4611619471yui_3_16_0_ym19_1_1522254102299_21107"><br clear="none"></div><div id="yiv4611619471yui_3_16_0_ym19_1_1522254102299_21107">For those with 36v systems, what charger are you using? How many amps? How long to charge the bank of batteries?</div><div id="yiv4611619471yui_3_16_0_ym19_1_1522254102299_21107"><br clear="none"></div><div id="yiv4611619471yui_3_16_0_ym19_1_1522254102299_21107"><br clear="none"></div></div></div></div>_______________________________________________<br clear="none">Personal_Submersibles mailing list<br clear="none"><a rel="nofollow" shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org" target="_blank" href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><br clear="none"><a rel="nofollow" shape="rect" target="_blank" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br clear="none"></div>
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