Shares of Westwater Resources Inc. /zigman2/quotes/209450453/composite WWR -9.93% more than doubled (up 116%) in very active trading Tuesday, after the battery-materials company announced positive results of an independent test of its ULTRA-PMG battery graphite material. Trading volume ballooned to 3.2 million shares, compared with the full-day average of about 175,300 shares. The company said resistivities achieved by ULTRA-PMG from the first simulation samples "were very desirable," with results showing "superior or comparable" resistivity values reported by other manufacturers. "We have shown that one of the key products in our business plan - purified micronized graphite (ULTRA-PMG) - can be produced using proprietary processes that we intend to utilize in our pilot program later this year," said Chief Executive Christopher Jones. "Successful performance testing demonstrates that we can manufacture our ULTRA-PMG as a premium-grade, conductive enhancement material for all types of batteries at larger scale."