The present application claims priority to Chinese patent application No. CN201410313608.X filed on Jul. 3, 2014, which is incorporated herein by reference in its entirety.
The present disclosure relates to the technical field of electrochemical energy storage devices, and particularly relates to a preparation method of a non-rectangular laminated cell.
Lithium-ion batteries have been more and more widely used in the fields of mobile electronic devices, electric vehicles, energy storage and the like as the most representative electrochemical energy storage devices in the new energy field. As an arrangement of many electronic components in a mobile electronic device always appears as a step profile or other irregular profile, a space left for placing a battery is not always regular rectangular, but lithium-ion batteries are generally regular rectangular in the prior art, when such a lithium-ion battery is used in the mobile electronic device, a part of an inner space of the mobile electronic device is usually idle and is wasted. Therefore, the industry have proposed a non-rectangular battery so as to improve efficient use of the space of the mobile electronic device from the battery, thus the mobile electronic device having the same dimension can achieve better volume and energy effects from the non-rectangular battery. However, because the above non-rectangular battery has a special shape, the preparation process of the non-rectangular battery is complex and has a low efficiency.
At present, a preparation process of a non-rectangular lithium-ion cell is divided into the following two modes:
(1) Laminated-type cell, a positive electrode plate and a negative electrode plate are cut to form plate shapes which have predetermined and different size and/or shape, then a separator is inserted between the cut positive electrode plate and the cut negative electrode plate, thereby obtaining the non-rectangular laminated cell, the separator described herein may be a plate shape, a Z shape or a wound shape corresponding to the electrode plate.
(2) Wound-type cell, a positive electrode plate and a negative electrode plate are cut to form a predetermined shape, then a winding process is adopted to obtain the non-rectangular lithium-ion cell.
In a conventional preparation process of the non-rectangular lamination-type cell, the positive electrode plate and the negative electrode plate which are different in size and/or shape needs to be laminated in a predetermined order, operation is relatively complex, production efficiency needs to be improved, and it is required for higher calibration performance and other performances of a production device.
In view of the problem existing in the background, an object of the present disclosure is to provide a preparation method of a non-rectangular laminated cell, which can greatly improve the efficiency of the preparation of the non-rectangular laminated cell.
In order to achieve the above objects, the present disclosure provides a preparation method of a non-rectangular laminated cell which comprises steps of: preparing k kinds of laminated cell units, in the k kinds of laminated cell units, there are at least two kinds of laminated cell units adopting different electrode plate assemblies which are different in shape and/or size in preparing the laminated cell units; preparing a non-rectangular laminated cell: laminating the k kinds of laminated cell units in a predetermined order, so as to obtain the non-rectangular laminated cell. The preparation of the i-th (i=1, 2 . . . k) kind of laminated cell unit comprises substeps of: providing a laminated pack: the laminated pack comprises ni laminated groups, the each laminated group comprises mi electrode plate assemblies which are the same in shape and size and the numbers of the electrode plate assemblies of all the laminated groups are the same or different, and ni≧2, mi≧2, a spacer is provided between the adjacent laminated groups, the electrode plate assemblies of all the laminated groups of the laminated pack and the spacers between the adjacent laminated groups are orderly positioned in a Z-shaped separator in a laminating direction, an upper part and a lower part of the separator adjacent to the each spacer are separated by the spacer; and forming a laminated cell unit: the separator is broken at an end of the each spacer positioned in the separator to allow the each spacer and the each laminated group to be separated from each other, so as to obtain the corresponding laminated cell unit formed by the electrode plate assemblies of the each laminated group and a corresponding part of the separator; the each laminated cell unit comprises a positive electrode plate and a negative electrode plate, or a mono-cell, or combination of the mono-cell and the positive electrode plate and/or the negative electrode plate; the positive electrode plate, the negative electrode plate, the mono-cell are collectively referred to as the electrode plate assembly; the mono-cell is composed of the positive electrode plate, the negative electrode plate, and another separator between the positive electrode plate and the negative electrode plate; the positive electrode plate is provided with a positive electrode tab, the negative electrode plate is provided with a negative electrode tab, the positive electrode tab and the negative electrode tab of the each laminated cell unit are provided on the same side or different sides in a direction perpendicular to the laminating direction of the laminated pack and a folding direction of the Z-shaped separator.
The present disclosure has the following beneficial effects:
In the preparation of the k kinds of laminated cell units and in the preparation of the i-th (i=1, 2 . . . k) kind of laminated cell unit, by that the spacer is adopted, a plurality of laminated groups can be provided in one laminated pack, the separator is broken at the end of the each spacer positioned in the separator, therefore, the each spacer and the each laminated group can be separated from each other, so as to form a plurality of laminated cell units, in this way, an auxiliary time is saved, thereby greatly improving the efficiency of the preparation of the laminated cell unit adopting the Z-shaped separator, the non-rectangular laminated cell is obtained by laminating the obtained laminated cell units in a predetermined order, so that the efficiency of the preparation of the non-rectangular laminated cell is greatly improved.
The organization and manner of the structure and operation of the present disclosure, together with further objects and advantages thereof, may best be understood by reference to the following description, taken in connection with the accompanying Figures, wherein like reference numerals identify like elements, and in which:
Reference numerals of the embodiments are represented as follows:
The detailed description that follows describes exemplary embodiments and is not intended to be limited to the expressly disclosed combination(s). Therefore, unless otherwise noted, features disclosed herein may be combined together to form additional combinations that were not otherwise shown for purposes of brevity.
Referring to
The preparation of the i-th (i=1, 2 . . . k) kind of laminated cell unit comprises substeps of: providing a laminated pack: the laminated pack SPi comprises ni laminated groups SGi, the each laminated group SGi comprises mi electrode plate assemblies which are the same in shape and size and the numbers of the electrode plate assemblies of all the laminated groups SGi are the same (referring to
Here, it should be noted that, in the practical production, because the separator SEi may be in the case of continuous unwinding, for this case, the separator SEi can be cut off at a laminating tail end of the laminated pack SPi after completion of providing the laminated pack SPi; of course it is not limited to that, if a length of the separator SEi is provided precisely, the separator SEi does not have to be cut off at the laminating tail end of the laminated pack SPi, in other words, the length of the separator SEi just meets the requirements of the laminated pack SPi.
In addition, in order to prevent loosening of the laminated groups SGi of the laminated pack SPi preferably, an end portion of the electrode plate assembly and an end portion of the spacer GTi positioned in the Z-shaped separator SEi along the folding direction F all contact the separator SEi, that is the end portions are surrounded by and in contact with the separator SEi. Of course it is not limited to that, the end portion of the electrode plate assembly and the end portion of the spacer GTi positioned in the Z-shaped separator SEi along the folding direction F may not be in contact with the separator SEi, that is the end portions are surrounded by but not in contact with the separator SEi according to the practical production situation (referring to
In the preparation method of the non-rectangular laminated cell according to the present disclosure, by that the spacer GTi is adopted, a plurality of laminated groups SGi can be provided in the laminated pack SPi, the separator SEi is broken at the end of the each spacer GTi positioned in the separator SEi, so that the each spacer GTi and the each laminated group SGi can be separated from each other, so as to form a plurality of laminated cell units SCi, thereby greatly improving the efficiency of the preparation of the laminated cell unit SCi adopting the Z-shaped separator SEi. Here, it should be noted that, the each spacer GTi and the each laminated group SGi are separated from each other as long as the separator SEi is broken at the end of the each spacer GTi positioned in the separator SEi without the need for pulling the each spacer GTi out.
In the step of providing the laminated pack in the preparation of the i-th (i=1, 2 . . . k) kind of laminated cell unit, the manners for providing the laminated pack may include following two manners according to manners for forming the Z-shaped separator SEi.
In an embodiment, referring to
In an embodiment, referring to
In an embodiment, in the substep of providing the laminated pack of the step of preparing the i-th (i=1, 2 . . . k) kind of laminated cell unit, the laminating order of the electrode plate assemblies of different laminated groups SGi are the same (referring to
In an embodiment, referring to
In an embodiment, referring to
In the substep of providing the laminated pack of the step of preparing the i-th (i=1, 2 . . . k) kind of laminated cell unit, a material of the separator SEi may be selected from at least one of vinyl polymer and vinyl copolymer, polyimide, polyamide, polyester, cellulose derivative, and polysulfonate. When the material of the separator SEi is selected from vinyl polymer and vinyl copolymer, the separator SEi may be a PP separator, a PE separator or a PP/PE/PP three-layer composite separator.
In an embodiment in the substep of providing the laminated pack of the step of preparing the i-th (i=1, 2 . . . k) kind of laminated cell unit, at least a surface of the separator SEi may be provided with an adhesive coating. In an embodiment, the adhesive coating contains polyvinylidene fluoride (PVDF). In an embodiment, the adhesive coating further contains inorganic particles. The inorganic particle may be Al2O3 or SiO2.
In an embodiment, in the substep of providing the laminated pack of the step of preparing the i-th (i=1, 2 . . . k) kind of laminated cell unit, a stiffness of a material of the spacer GTi may be 50 GPa˜2000 GPa, of course it is not limited to that, as long as the each spacer GTi has a strength that the spacer GTi is not plastically deformed when the spacer GTi is subjected to the pressure of a pressing mechanism PS (later described). In an embodiment, the material of the spacer GTi may be a metal or an organic resin. The metal may be selected from aluminum (Al) or stainless steel. The organic resin may be acrylic resin.
In an embodiment, referring to
Of course it is not limited to that, in the substep of providing the laminated pack of the step of preparing the i-th (i=1, 2 . . . k) kind of laminated cell unit, the length LGTi of the each spacer GTi may be smaller than the width WSEi of the separator SEi, the WGTi of the each spacer GTi may be smaller than the maximum width of the electrode plate assemblies of the two adjacent laminated groups SGi located above and below, as long as the each spacer GTi separates the upper part and the lower part of the adjacent separator SEi.
In an embodiment, referring to
In the preparation method of the non-rectangular laminated cell according to the present disclosure, referring to
In an embodiment, in the substep of pressing the laminated pack of the step of preparing the i-th (i=1, 2 . . . k) kind of laminated cell unit, the pressing mechanism PS is a hot press mechanism, and hot pressing is performed on the laminated pack SPi using the hot press mechanism. In an embodiment, a hot pressing temperature adopted by the hot press mechanism is 50° C.˜200° C., a hot pressing pressure adopted by the hot press mechanism is 0.1 MPa˜1.5 MPa, a hot pressing time by the hot press mechanism is 1 s˜120 s. Furthermore, when at least a surface of the separator SEi is provided with the adhesive coating, during the substep of pressing the laminated pack of the step of preparing the i-th (i=1, 2 . . . k) kind of laminated cell unit, when the pressing mechanism PS presses the laminated pack SPi along the laminating direction S, the electrode plate assemblies of the each laminated group SGi of the laminated pack SPi and the corresponding separator SEi are bonded together by adhering via an adhesive in the adhesive coating, but the each spacer GTi and the adjacent separator SEi and the adhesive in the adhesive coating are not bonded to each other, so that the each spacer GTi and the adjacent separator SEi are not bonded together. The structure of the each laminated group SGi after pressing is more stable based on the adhesive coating, so that it is easier to separate the each spacer GTi and the adjacent separator SEi to obtain the each laminated cell unit SCi, and it is easier to perform pick-up operation on the obtained laminated cell unit SCi. Preferably, in order to better ensure that the each spacer GTi and the adjacent separator SEi and the adhesive in the adhesive coating are not adhered to each other, in an embodiment, an upper surface and a lower surface of the each spacer GTi each may be provided with an anti-adhesive coating.
Here, it should be noted that, the “bonded” refers to that the electrode plate assembly of the each laminated group SGi of the laminated pack SPi and the corresponding separator SEi are combined to each other without detaching, so as to allow the structure of the each laminated group SGi to be regular and stable. And “not bonded” refers to that the each spacer GTi and the adjacent separator SEi are not combined together, so that it is easier to separate the each spacer GTi and the adjacent separator SEi from each other, so as to separate the each laminated group SGi.
In the preparation method of the non-rectangular laminated cell according to the present disclosure, the step of preparing the i-th (i=1, 2 . . . k) kind of laminated cell unit further comprises a substep after the substep of forming the laminated cell unit: performing hot pressing on the obtained laminated cell unit SCi using a hot press mechanism. Furthermore, a hot pressing temperature adopted by the hot press mechanism is 50° C.˜200° C., a hot pressing pressure adopted by the hot press mechanism is 0.1 MPa˜1.5 MPa, a hot pressing time adopted by the hot press mechanism is 1 s˜120 s, so as to stabilize the structure of the laminated cell unit SCi.
The present disclosure provided herein describes features in terms of specific and exemplary embodiments thereof. Numerous other embodiments, modifications and variations within the scope and spirit of the appended claims will occur to persons of ordinary skill in the art from a review of this disclosure.
Number | Date | Country | Kind |
---|---|---|---|
201410313608.X | Jul 2014 | CN | national |