Abstract: The present application provides a rolled core and a battery, where the rolled core includes a positive electrode piece having a paste-removal portion of positive electrode piece, and a negative electrode piece including a negative current collector, a negative active material layer, and a gap filling body; the paste-removal portion of positive electrode piece is a missing part of the positive electrode piece relative to the negative electrode piece at a winding-start end of the rolled core; the negative current collector includes a first side and a second side which are opposite to each other, and at least one of the first side and the second side is provided with a negative active material layer; the gap filling body is arranged on one of the first side and the second side at a position corresponding to the winding-start end of the rolled core.

Abstract: This application provides an electrode sheet and an electrochemical device. The electrode sheet includes a current collector and a functional coating located on at least one surface of the current collector. The functional coating includes a first coating, a second coating and an active material layer that are sequentially stacked on a surface of the current collector. The first coating includes a conductive agent, a binder and a first functional filler, and the second coating includes a conductive agent, a binder and a second functional filler. A mass ratio of the binder in the first coating to the first coating is a1, a mass ratio of the binder in the second coating to the second coating is a2, and a mass ratio of the binder in the active material layer to the active material layer is a3, and a1>a2>a3.

Abstract: This application provides an electrode sheet and an electrochemical device. The electrode sheet includes a substrate. The substrate includes a current collector and a protective layer provided on a surface of the current collector. An active material layer is further provided on the protective layer. The protective layer includes a non-active material including an inorganic material. The inorganic material has a weight loss rate of a measured by a thermogravimetric analysis, where 0.1%?a?10%, a=(m0?m1)/m0, m0 is a mass of the inorganic material before the thermogravimetric analysis, and m1 is a mass of the inorganic material after the thermogravimetric analysis. The mass after the thermogravimetric analysis is a mass of the inorganic material when its temperature is raised from 25±5° C. to 900±20° C. at a heating rate of 20±2° C./min under an inert atmosphere.

Abstract: Disclosed are a battery and an electronic device, where the battery includes a first electrode plate, a second electrode plate, a control unit, and a first tab and a second tab that are connected to the first electrode plate, and the first electrode plate and the second electrode plate have opposite polarities. The control unit includes a heating control circuit, and in a case that the battery is connected to an external power supply, the heating control circuit is configured to: when a battery temperature of the battery is less than a first temperature threshold, conduct the first tab, the first electrode plate, and the second tab to heat the battery. A charging speed of the battery at a low temperature may be improved, and lithium deposition and capacity fading of the battery may be slowed down.

Abstract: An electrode piece, a rolled core and a battery, where the electrode piece includes a current collector and an active substance layer; the electrode piece has a single-sided area and a double-sided area, the single-sided area is located on a side of the electrode piece along a length direction thereof, a surface of one side of the current collector in the single-sided area is covered with the active substance layer, while surfaces of both sides of the current collector in the double-sided area are covered with the active substance layer; and multiple tabs protrude from one side of the electrode piece along a width direction thereof, and are spaced apart; in the single-sided area, an anti-rolling strip is provided on a surface of a side of the current collector not covered by the active substance layer, and is disposed on the same side as the tabs.

Abstract: A communication method and apparatus are provided. The method includes: A terminal device sends first data to a network device through a first cell group in an activated state. The terminal device receives a first message from the network device, where the first message is used to deactivate the first cell group. The terminal device changes a state of the first cell group from the activated state to a deactivated state based on the first message of the network device. If the terminal device receives no success acknowledgment of the first data and/or there is second data that has not been transmitted in the first cell group, the terminal device retransmits the first data and/or sends the second data to the network device through a second cell group in an activated state.

Abstract: A 3D printing device includes a liquid bath configured to contain liquid resin and having a main area and an extending area; a printing platform configured to carry a printed sample and inserted into the main area; and a release film assembly including a release film and a release film driving unit for driving the release film to move horizontally between the main area and the extending area. The invention has the following beneficial effects: 1, various errors caused by use of a quick levelling component such as a hub are eliminated, thus improving the printing quality; 2, an accurate printing thickness can be obtained by horizontally pushing printing liquid once by the release film, thus improving the printing efficiency; and 3, when the printing platform is assembled or disassembled, the release film can move to the extending area and does not need to be disassembled, so operation is simplified.

Abstract: Disclosed are a positive electrode plate and a battery. A relationship is established between a thickness of an electrode plate, distribution of lithium cobalt oxide with a structure of different contents of element aluminum, and full battery cycling performance. That is, based on a thickness of the electrode plate, lithium cobalt oxide with an appropriate content of the element aluminum is selected, and distribution in a thickness direction of the positive electrode plate is changed, so that the content of Al in the thickness direction of the electrode plate generally presents a distribution trend of less content of Al in a bottom layer and more content of Al in a top layer. In this way, a problem of deterioration of high temperature cycling of a lithium-ion battery due to decreased structural stability of existing lithium cobalt oxide may be solved.

Abstract: A 3D printing device includes a liquid bath, a printing platform, a release film assembly, a levelling hob assembly, and a bubble scraper. One side of the liquid bath is widened to form an extending area. The bubble scraper is disposed in the extending area, fixed at the bottom of the extending area, and located at a side close to a main area. The release film assembly and the levelling hob assembly are capable of moving horizontally. The invention has the following beneficial effects: 1. manual operations before and after printing are reduced and simplified; 2. the risk of damage to a levelling hob caused by frequent manual assembly and disassembly is lowered, and the waste of time caused by repeated levelling of the hob due to reassembly of the levelling hob is reduced; 3. the risk of contamination caused by dripping of the liquid resin is lowered.

Abstract: A device for keeping the liquid level constant during 3D printing includes a liquid bath for containing printing liquid, a printing platform for carrying a printed sample, a liquid level counterbalance inserted into the liquid bath, and a link mechanism connected with the printing platform and the liquid level counterbalance respectively for driving the liquid level counterbalance to ascend when the printing platform descends. The printing platform is inserted into the liquid bath and driven by a lifting device to ascend or descend. The printing platform and the liquid level counterbalance are in a relationship that a volume of a portion of the printing platform immersed into the printing liquid due to descending of the printing platform is equal to a volume of a portion of the liquid level counterbalance leaving the printing liquid due to rising of the liquid level counterbalance caused by descending of the printing platform.

Abstract: A laser wireless power transmission device and method based on power acquisition on power line. The device includes a power transmitter and a power receiver both installed on a power transmission line. The power transmitter includes an online induction power acquisition module, a semiconductor laser, a communication module, a two-dimensional pan-tilt, a beam shaping module, a control unit, a video image module, and an IMU module. The power receiver includes a four-quadrant photovoltaic panel, a DCDC module, a wireless monitoring module, and a battery.

Abstract: A method for producing a fuel oil includes the steps of (1) bringing a sulfur-containing feedstock oil and an alkali metal into contact for a pre-reaction to obtain a pre-reaction material, wherein the pre-reaction is performed under hydrogen-free conditions; (2) bringing the pre-reaction material into contact with a hydrogen-supplying agent for a hydrogenation reaction; and (3) separating the material obtained in step (2) to obtain a liquid-phase product fuel oil and a solid mixture. Using this method, inferior and cheap feedstock oils, such as heavy residual oils, can be converted into fuel oils.

Abstract: An electrode sheet, a preparation method thereof, and a lithium ion battery are provided in this application. The electrode sheet includes a current collector, an active material layer and a tab piece; the current collector comprises a base layer, and first and second conductive layers; the current collector is divided into first and second zones; the tab piece is connected to the second zone of the current collector; the second zone is provided with a through hole for enabling opposite sides of the current collector to be communicated with each other; one part of structure of the tab piece is connected to the first conductive layer, and the other part of structure of the tab piece extends through the through hole to a side of the current collector opposite to the first conductive layer and is connected to the second conductive layer.

Abstract: Disclosed is a battery, which includes a jelly roll. The jelly roll includes a first electrode plate, a separator, and a second electrode plate; the first tab is close to a first bending portion of a first end of the jelly roll, the second tab is close to a second bending portion of a second end of the jelly roll, a winding tail end of the jelly roll covers the first bending portion, and the winding tail end extends in a direction from the first bending portion to the second bending portion; and an outer side of the jelly roll includes a first outer adhesive paper, a region between a head of the second end of the jelly roll and the second tab directly faces a first portion of the jelly roll, and the first outer adhesive paper covers at least one side surface of the first portion.

Abstract: A jelly roll includes a negative electrode plate, along a winding direction, an inner surface of a second bending region of the negative electrode plate is covered by a first tape layer, and in a thickness direction of the jelly roll, a projection of two ends of the first tape layer is connected to or partially overlapped with a projection of a winding head of the negative electrode plate. As a result, surface unevenness of the jelly roll is improved, thereby improving the flatness of a battery cell.

Abstract: Disclosed are an electrode plate and an electrochemical apparatus. A first function surface of a current collector in the electrode plate includes a first active layer region and a first tab region, a second function surface of the current collector includes a second active layer region corresponding to the first active layer region and a second tab region corresponding to the first tab region, and an active layer is disposed in the first active layer region and/or the second active layer region. The first tab region is provided with N through holes penetrating to the second tab region, a tab passes through a through hole, and a first section of the tab is connected to the first tab region to form a first connection region and a second section of the tab is connected to the second tab region to form a second connection region, where N?1.

Abstract: Disclosed are a positive electrode plate and a lithium-ion battery including the same. The positive plate includes a positive electrode current collector and a positive electrode coating layer; and the positive electrode coating layer includes a first coating layer and a second coating layer, wherein the first coating layer is coated on the positive electrode current collector surface, and the second coating layer is coated on the first coating layer surface. The lithium-ion battery has a good safety performance, and when mechanical misuse (needling, weight impact) occurs, the probability of battery fire failure is significantly reduced.

Abstract: Disclosed is a lithium ion battery. The lithium ion battery includes a positive electrode plate, a negative electrode plate and a separator. The positive electrode plate, the separator and the negative electrode plate are stacked successively and then wound from inside to outside. The positive electrode plate includes a positive electrode current collector. At least one functional surface of the positive electrode current collector is provided with a protective layer. A surface of the protective layer away from the positive electrode current collector is provided with a positive electrode active layer. A length of the protective layer is greater than a length of the positive electrode active layer in a winding direction of the positive electrode current collector. According to the present application, by increasing a protection area of the protective layer for a positive electrode current collector, safety performance of the lithium ion battery is improved.

Abstract: The present disclosure provides a negative electrode piece, a preparation method thereof and a lithium-ion battery including the negative electrode piece. The negative electrode piece includes a negative electrode current collector, a first negative electrode active material layer, a second negative electrode active material layer, and a negative electrode tab, where the negative electrode tab is arranged on a surface of one side of the negative electrode current collector, and a surface of one side of the negative electrode current collector near the negative electrode tab and providing with the negative electrode tab is coated with the first negative electrode active material layer, a surface of one side of the negative electrode current collector away from the negative electrode tab and providing with the negative electrode tab is coated with the second negative electrode active material layer.

Abstract: The present disclosure provides an electrode sheet and a lithium-ion battery. A first aspect of the present disclosure provides an electrode sheet, including a current collector, and a first active layer and a second active layer which are sequentially stacked on a surface of the current collector; where, the first active layer is provided with a first groove, the second active layer is provided with a second groove, and a vertical projection of the second groove on the current collector covers a vertical projection of the first groove on the current collector; a tab is disposed at the first groove and is electrically connected with the current collector. The electrode sheet provided by the present disclosure effectively improves the charging risk at a tab connection position and increases the cycle retention rate of the lithium-ion battery under the condition of maintaining high-rate charging.