{"id":12581,"date":"2020-08-23T13:54:16","date_gmt":"2020-08-23T20:54:16","guid":{"rendered":"http:\/\/cafe.foundation\/blog\/?p=12581"},"modified":"2020-08-23T13:54:16","modified_gmt":"2020-08-23T20:54:16","slug":"oxis-batteries-to-fly-in-two-airplanes","status":"publish","type":"post","link":"http:\/\/cafe.foundation\/blog\/oxis-batteries-to-fly-in-two-airplanes\/","title":{"rendered":"Oxis Batteries to Fly in Two Airplanes"},"content":{"rendered":"

While we wait yet another five years for commercial development of each newly announced but promising battery chemistry, one company has its cells ready to fly in Bye Aerospace\u2019s eFlyer 2 and in Texas Aircraft\u2019s Colt S-LSA.\u00a0 Oxis Energy has managed to leapfrog lithium-ion makers with its lithium-sulfur battery packs packing 400 Watt-hours per kilogram.\u00a0 Considering the best announced pack-level li-ion performance has been 260 W-hr\/kg, the leap is significant.<\/p>\n

Batteries, for now, are at the heart of electric aircraft.\u00a0 Until Doc Brown\u2019s Flux Capacitor or a hydrogen fuel cell with Dollar Tree refills comes along, batteries are battling it out for our airborne dollars.\u00a0 Lithium-ion remains in the forefront, with Tesla staging its shareholders\u2019 meeting and its long-anticipated \u201cBattery Day\u201d<\/a> on September 22.\u00a0 Elon Musk has been dangling the promise of a million-mile battery for the last year, which may tie in with Chinese manufacturer Contemporary Amperex Technology (CATL).\u00a0\u00a0 According to Bloomberg, CATL\u2019s, \u201cChairman and founder Zeng Yuqun said the company is ready with a battery pack that’ll last 1.2 million miles<\/a> before needing to be replaced.\u201d\u00a0 Ostensibly, Tesla is a customer.<\/p>\n

Discounting the lack of performance data and despite a ten-percent price differential over existing Li-ion cells, CATL\u2019s batteries may be good investments for the long haul.\u00a0 Most electric vehicles currently come with an eight-year, 120,000-mile warranty, so ten percent more for 10 times the mileage and a potential eighty years\u2019 usage is a bargain.\u00a0 (Your batteries will outlast you and your parrot.)<\/p>\n

Overcoming the Longevity Gap<\/strong><\/h4>\n

Longevity has been a big issue with lithium-sulfur so far.\u00a0 Mark Crittenden<\/a>,\u00a0head of battery development and integration at Oxis Energy, explains that lithium-sulfur cells tend to degrade in a different way than lithium-ion cells, described concisely in his IEEE Spectrum article<\/a>.<\/p>\n

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Oxis in cell, pack and casing formats, adding weight to provide protective shielding to cells<\/p><\/div>\n

The Oxis Energy Technology page<\/a> indicates a cell life of 250 charge\/discharge cycles (the company hopes to double this to 500 cycles \u201cwithin the next two years.\u201d\u00a0 Even given the low number, the average light aircraft in this country flies only about 80 hours per year (a terrible utilization rate) and the average light aircraft pilot flies only 40-80 hours.\u00a0 Even business craft average only about 30 hours per quarter.<\/a>\u00a0 This would give about three years\u2019 use at 250 cycles or six years at 500.\u00a0 If as claimed Oxis batteries are substantially less expensive than Li-ion equivalents, this may be to their advantage.<\/p>\n

Other Benefits<\/strong><\/h4>\n

Oxis demonstrates their batteries\u2019 ability to take bullets and nail punctures while remaining fully active and not bursting into flames \u2013 something with which Li-ion cells don\u2019t fare so well.<\/p>\n