RE: NGC Completes Further Successful Testing of Ba - NRC reported that the electrochemical performance of the uncoated samples provided by Northern performed very well compared to commercial coated synthetic samples, especially considering their early stage of development.
- The overall objectives of the program were to evaluate, quantify and compare the performance of six different samples of uncoated spherical graphite provided by Northern to each other and to two commercial, coated synthetic reference samples.
- Northern has achieved spherical graphite yields of up to 70% on rounding when starting with its large flake. Almost all non-synthetic spherical graphite is made from small -100 mesh flake in China and yields are only about 30%. Different size fractions were produced for testing and they were purified both by Northern's proprietary process and by a commercial industry process.
- Three of the Northern samples showed a slightly higher irreversible capacity, 28 mAh/g, than the synthetic reference sample at 25mAh/g. This is very promising for uncoated graphite as performance could be improved by coating which is standard industry practice for natural graphite.
- Northern's uncoated graphite had 24% higher capacity after 50 charge/discharge cycles than either of the commercial coated synthetic anode materials.
- the surface area could be improved by a coating procedure and this will be a second stage of testing at NRC.
- Tap Density can also be improved through coating.
- There was no evidence of impurities that might affect battery performance in five of the samples.
- Overall, samples purified with Northern's proprietary process performed better than those purified with the commercial process.