Structured aqueous processed lignin-based NMC cathodes for energy-dense LIBs with improved rate capability

The cost and environmental impact of lithium-ion batteries (LIBs) can be reduced substantially by enabling the aqueous processing of cathode materials. For the first time, we fabricate high-density, thick NMC111 cathode coatings using water as a solvent, and bio-derived kraft lignin as a binder material. The performance deterioration at high discharge currents is amplified by high mass loading and low bulk porosity. At porosities higher than 60%, the electronic conductivity limits the rate capability of the cathode, while for porosities lower than 30%, ionic conduction causes significant ionic polarization and consequently diminishes rate performance. The underlying lithium-ion diffusion limitation at current densities higher than 0.2 C is mitigated by creating line structures on the surface of the cathode. Structuring the half-dried cathode surface with ceramic blades is preferred over a stamp-like silicon wafer, and the line structures are easier to produce with high mechanical stability in comparison to pit structures. The lignin/water cells investigated herein restore after undergoing rate capability tests (5C), except those with pit structures or ultra-high thickness (>200 μm), due to the extensive crack formation during water evaporation which causes poor mechanical stability. Mechanical and laser structuring methods are compared on the surface of a PVDF/NMP-based cathode. Concerning the implementation in a large-scale battery factory, mechanical structuring is currently considered a processing of choice as it has no surface residuals or waste material. However, laser structuring with ultra-short pulses technique has the potential of outperforming mechanical structuring if the process is optimized to high precision to reduce residual and waste material, due to reproducibility and lower operational costs

Insulin-like growth factor-I and prostate cancer: a meta-analysis

Some, but not all, epidemiological found have shown that high circulating levels of insulin-like growth factor-I (IGF-I) are associated with an increased risk of prostate cancer. We performed a meta-analysis on all the studies reported so far to evaluate this association. In our Medline search, 14 case–control studies were identified. A standard protocol abstracted information for each study. Hedges' standardized mean difference (HSMD) and odds ratio (OR) were used to estimate the effect of IGF-I and IGF-binding proteins (IGFBP-3). The combined data showed that circulating levels of IGF-I were significantly higher in prostate cancer patients (HSMD = 0.194). The OR for prostate cancer was 1.47 (95% confidence interval (CI) 1.23–1.77) among men with high IGF-I compared to those with low IGF-I. The OR was 1.26 (95% CI 1.03–1.54) for IGFBP-3. Circulating levels of IGF-I and IGFBP-3 are likely to be higher in prostate cancer patients than in the controls. These findings support the suggestion that high IGF-I and IGFBP-3 are associated with an increased risk of prostate cancer. © 2001 Cancer Research Campaignhttp://www.bjcancer.co