I said >> While the assumptions behind that blanket figure would need to be examined on a case by case basis when high discharge and long [tm] life of LiPo cells is required ... A friend said > > The ratio active volume/casing area must be critical to the 6W/A-hr rule > of thumb. Thus it would apply only to a range of cells with construction > and dimensions sensibly similar to whatever cells were tested I think. > > So ... Their aim is to address that point in the real world range of applications that are of interest to them First read page 5 http://www.maac.ca/docs/2013/lipo_batteriesinternal_resistance_max_current_= draw_true_crating__rev3_toc.pdf Leading to: You could read page 55 here for introduction or skip it http://www.maac.ca/maacmag/magazines/2013/MAC_Jan_2013.pdf Getting closer http://www.rcgroups.com/forums/showthread.php?t=3D1577989 Then: http://www.rcgroups.com/forums/showthread.php?t=3D1578001#post20484169 The purpose of this thread is to serve as a central repository for objective performance data for commercially available lithium polymer (lipoly) battery packs based on real world performance rather than the flawed manufacturer 'C' rating system. Besides manufacturer 'C' rating (maximum current that a pack can be expected to sustain throughout a full discharge), modelers have had to rely on advice from fellow modelers, scattered various test threads, etc., from which to cull meaningful information to make lipoly purchase decisions. It is hoped that this thread will be an additional source of reliable data that is performance based, not marketing based. In order to make the data as accessible as possible and provide the modeler with a true indication of how a pack will perform in an actual application, Wayne Giles, John Julian, and myself have developed and validated a simple tool (MS Excel, attached below) that calculates the maximum recommended current, FOM, and True C rating for a lipoly pack based upon the pack's capacity and measured cell internal resistance. A web-based version of the tool is available here: http://www.jj604.com/LiPoTool/. Live links (when they left here) * thread.* [image: image icon] FilesView all Files in thread - Lipoly Objective Performa... Lipoly Performance Calculation Tool. Simply download a... (10.0 KB) 361 views ZIP - Compiled Lipoly Performan... Compiled results. Download and unzip and open in MS Ex... (19.8 KB) 533 views ZIP - Compiled Lipoly Performan... Compiled results. FOM sorted. PDF format. (20.7 KB) 1106 views PDF - Compiled Lipoly Performan... Compiled results. FOM sorted. Excel format. (21.6 KB) 499 views ZIP - Lipoly Objective Performa... Tool for small lipolys adds resolution to Max. Current ... (5.4 KB) 167 views ZIP [image: mrforsyth is offline] [image: Find More Posts by mrforsyth] [image: RCG Plus Member] or: http://www.rcgroups.com/forums/showpost.php?p=3D20484199&postcount=3D5 Related graphs - see various texts. http://static.rcgroups.net/forums/attachments/6/9/1/2/6/a4567703-189-Temper= ature%20and%20IR.PNG http://static.rcgroups.net/forums/attachments/6/9/1/2/6/a4567719-115-3x%20c= ells%2020C.png :-) http://static.rcgroups.net/forums/attachments/6/9/1/2/6/a4567712-243-Hyperi= on%20160%20at%2010-25C.PNG ! .... R > > > http://www.maac.ca/docs/2013/lipo_batteriesinternal_resistance_max_curren= t_draw_true_crating__rev3_toc.pdf > > > --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .