Editing Cold fusion (section)

====Loading ratio====
[[File:Gas-ColdFusionCell-SRI-Intl-McKubre.jpg|thumb|upright|Michael McKubre working on deuterium gas-based cold fusion cell used by [[SRI International]]]]

Cold fusion researchers ([[Michael McKubre|McKubre]] since 1994,{{sfn|ps=|Simon|2002|pp=145–148}} [[Italian National Agency for New Technologies, Energy and Sustainable Economic Development|ENEA]] in 2011<ref name=ENEA_Magazin/>) have speculated that a cell that is loaded with a deuterium/palladium ratio lower than 100% (or 1:1) will not produce excess heat.{{sfn|ps=|Simon|2002|pp=145–148}} Since most of the negative replications from 1989 to 1990 did not report their ratios, this has been proposed as an explanation for failed reproducibility.{{sfn|ps=|Simon|2002|pp=145–148}} This loading ratio is hard to obtain, and some batches of palladium never reach it because the pressure causes cracks in the palladium, allowing the deuterium to escape.{{sfn|ps=|Simon|2002|pp=145–148}} Fleischmann and Pons never disclosed the deuterium/palladium ratio achieved in their cells;{{sfn|ps=|Huizenga|1993|p=82}} {{As of|2002|lc=y}} there were no longer any batches of the palladium used by Fleischmann and Pons because the supplier changed the manufacturing process,{{sfn|ps=|Simon|2002|pp=145–148}} and researchers still had problems finding batches of palladium that achieved heat production reliably.{{sfn|ps=|Simon|2002|pp=145–148}}