The present application relates to a spirobifluorene derivative of a specific formula (I) which is suitable for use in electronic devices.

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A SiOC composite material in microparticulate form, wherein the microparticles are formed, in whole or in part, of an amorphous SiOC matrix with Si ranging from 20 wt % to 60 wt %, O from 20 wt % to 40 wt % and C from 10 wt % to 50 wt %, based on the total weight of the SiOC matrix, wherein amorphous or crystallized silicon particles are embedded within the SiOC matrix and wherein the microparticles are of core/coating structure with a core formed of the amorphous SiOC matrix and coated with at least one amorphous carbon layer; and to a method for producing such SiOC composite material. It also relates to an electrode active material, an electrode and a battery, especially a lithium-ion battery, including the aforementioned SiOC composite material.

A SiOC composite material in microparticulate form, wherein the microparticles are formed, in whole or in part, of an amorphous SiOC matrix with Si ranging from 20 wt % to 60 wt %, O from 20 wt % to 40 wt % and C from 10 wt % to 50 wt %, based on the total weight of the SiOC matrix, wherein amorphous or crystallized silicon particles are embedded within the SiOC matrix and wherein the microparticles are of core/coating structure with a core formed of the amorphous SiOC matrix and coated with at least one amorphous carbon layer; and to a method for producing such SiOC composite material. It also relates to an electrode active material, an electrode and a battery, especially a lithium-ion battery, including the aforementioned SiOC composite material.

Silicon anode compositions are provided which include embedded silicon carbide nanofibers. Methods of production and use are further described.

Disclosed are a secondary battery comprising a negative electrode composed of two or more negative electrode plates and a method of manufacturing the secondary battery, wherein each of the negative electrode plates includes a lithium by-product layer formed through pre-lithiation reaction on a negative electrode current collector coated with a negative electrode active material, wherein an inorganic substance layer is formed on a negative electrode tab that is extended from an end at one side of the negative electrode current collector and is composed of an active material-non-coated portion not coated with the negative electrode active material, and negative electrode tabs of the negative electrode plates are electrically connected with one negative electrode lead to form a negative electrode terminal.

Disclosed are a secondary battery comprising a negative electrode composed of two or more negative electrode plates and a method of manufacturing the secondary battery, wherein each of the negative electrode plates includes a lithium by-product layer formed through pre-lithiation reaction on a negative electrode current collector coated with a negative electrode active material, wherein an inorganic substance layer is formed on a negative electrode tab that is extended from an end at one side of the negative electrode current collector and is composed of an active material-non-coated portion not coated with the negative electrode active material, and negative electrode tabs of the negative electrode plates are electrically connected with one negative electrode lead to form a negative electrode terminal.

The negative electrode for an electric device includes a current collector and an electrode layer containing a negative electrode active material, a conductive auxiliary agent and a binder and formed on a surface of the current collector, wherein the negative electrode active material contains an alloy represented by the following formula (1): Si.sub.xSn.sub.yM.sub.zA.sub.a (in the formula (1), M is at least one metal selected from the group consisting of Al, V, C and a combination thereof, A is inevitable impurities, and x, y, z and a represent mass percent values and satisfy the conditions of 0<x<100, 0<y<100, 0<z<100, 0a<0.5, and x+y+z+a=100), and elastic elongation of the current collector is 1.30% or greater.

The negative electrode for an electric device includes a current collector and an electrode layer containing a negative electrode active material, a conductive auxiliary agent and a binder and formed on a surface of the current collector, wherein the negative electrode active material contains an alloy represented by the following formula (1): Si.sub.xSn.sub.yM.sub.zA.sub.a (in the formula (1), M is at least one metal selected from the group consisting of Al, V, C and a combination thereof, A is inevitable impurities, and x, y, z and a represent mass percent values and satisfy the conditions of 0<x<100, 0<y<100, 0<z<100, 0a<0.5, and x+y+z+a=100), and elastic elongation of the current collector is 1.30% or greater.

A multiple-atom silicon quantum dot is provided that includes multiple dangling bonds on an otherwise H-terminated in silicon surface, each dangling bonds having one of three ionization states of +1, 0 or 1 and corresponding respectively to 0, 1, or 2 electrons in a dangling bond state. The dangling bonds together in close proximity and having the dangling bond states energetically in the silicon band gap with selective control of the ionization state of one of the dangling bonds. A new class of electronics elements is provided through the inclusion of at least one input and at least one output to the multiple dangling bonds. Selective modification or creation of a dangling bond is also detailed.

A negative active material includes a silicon-based alloy, and the silicon-based alloy includes a Si single phase, a FeSi.sub.2 alpha phase, and a FeSi.sub.2 beta phase, wherein an intensity ratio of a second diffraction peak of the FeSi.sub.2 beta phase to a first diffraction peak of the FeSi.sub.2 alpha phase may be 0.1 or higher. A negative electrode includes the negative active material and a lithium battery includes the negative electrode. Lifespan characteristics of the lithium battery including the negative active material may improve.