Tanks such as these have been around a while, mainly for use with the fire department for air in smoke filled areas. While I agree that higher BAR/PSI would indeed allow for smaller tanks the BAR/PSI in the article is outside the range of most compressors today. As a gas blender myself our compressors top out at about 4700PSI. Keeping banks up at that level is not possible during the diving day and on occasion the recharge runs up until 10pm or after at out place. We have 4 banks 28x300 tanks total, 4 reserved for EAN. Consider also that most regulators are not raited for anything over 3500PSI and you will see that while this may be possible, is it worth the cost?
Just my .02cf worth
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