Patent Application: US-200913003063-A

Abstract:
the present invention concerns battery electrodes , and more particularly rechargeable lithium battery electrodes , with active materials , containing an inorganic binder for cohesion between the electrode materials and adhesion to a current collector . these electrodes are produced from an aqueous slurry of active electrode materials , optionally conductive additives and a soluble precursor or nanoparticles or a colloidal dispersion of the inorganic binder by spreading the slurry on a current collector and drying .

Description:
the present invention will be described in detail with examples supported by figures . fig1 shows electrochemical performance of limn 0 . 8 fe 0 . 2 po 4 / carbon nanocomposite electrode with 5 % lih 2 po 4 binder (♦) in comparison to 7 . 5 % pvdf binder (▴). fig2 shows the cycling stability of a battery with limn 0 . 8 fe 0 . 2 po 4 / carbon nanocomposite cathode containing 5 % lih 2 po 4 binder . the following examples are intended to be merely illustrative of the present invention , and not limiting thereof in either scope or spirit . a limn 0 . 8 fe 0 . 2 po 4 / carbon nanocomposite powder ( 1 g ) is dispersed with pistil and mortar in a solution of 50 mg lih 2 po 4 ( aldrich ) in 2 ml water . after addition of 0 . 1 ml ethanol for improved wetting the dispersion is spread with a doctor blade onto a carbon coated aluminum foil and dried in air up to 200 ° c . the thus obtained coating exhibits excellent adhesion even on bending of the foil . its electrochemical performance is equivalent to that with 7 . 5 % pvdf as binder ( fig1 ). a limn 0 . 8 fe 0 . 2 po 4 / carbon nanocomposite powder ( 1 g ) is dispersed with pistil and mortar in a solution of 50 mg sodium polyphosphate ( napo 3 ) n ( aldrich ) in 2 ml water . electrodes are prepared as described in example 1 and show similar performance . a limn 0 . 8 fe 0 . 2 po 4 / carbon nanocomposite powder ( 1 g ) is dispersed in a perl mill in a solution of 25 mg lih 2 po 4 ( aldrich ) and 25 mg li 2 si 5 o 11 ( aldrich ) in 4 ml water ( contrary to the strongly basic li 2 si 5 o 11 this solution has a neutral ph ). electrodes are prepared as described in example 1 and show similar performance . a limn 0 . 8 fe 0 . 2 po 4 / carbon nanocomposite powder ( 1 g ) is dispersed with pistil and mortar in a colloidal solution of 50 mg tio 2 of less than 15 nm average particle size in 2 ml water . electrodes are prepared as described in example 1 and show similar performance . a limn 0 . 8 fe 0 . 2 po 4 / carbon nanocomposite powder ( 3 g ) is dispersed in a perl mill in a solution of 75 mg lih 2 po 4 ( aldrich ) and 75 mg polyvinyl alcohol ( pva , 87 - 89 % hydrolyzed , average molecular weight 13000 - 23000 , aldrich ) in 12 ml water . the dispersion is spread with a doctor blade onto a carbon coated aluminum foil and dried in air up to 150 ° c . the thus obtained coating exhibits excellent adhesion even on bending of the foil . its electrochemical performance is equivalent to that with 7 . 5 % pvdf as binder . a limn 0 . 8 fe 0 . 2 po 4 / carbon nanocomposite powder ( 1 g ) is dispersed with pistil and mortar in a solution of 75 mg pvdf ( poly ( vinylidene fluoride )) in 2 ml nmp ( n - methyl - 2 - pyrrolidone ). the dispersion is spread with a doctor blade onto a carbon coated aluminum foil and dried in air up to 150 ° c . the electrochemical performance of the obtained electrode is shown for comparison in fig1 . 1 . guerfi , a ., kaneko , m ., petitclerc , m ., mori , m . & amp ; 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