Electrochemical device
An electrochemical device which includes an electrode plate and a porous layer formed on a surface of the electrode plate. The porous layer includes nanofibers and inorganic particles. The nanofibers and the inorganic particles are bonded together by a crosslinker. In addition, an electronic device, which includes this electrochemical device.
1 . An electrochemical device, comprising
an electrode plate; and
a porous layer on a surface of the electrode plate, wherein the porous layer comprises nanofibers and inorganic particles, the nanofibers and the inorganic particles are bonded together by a crosslinker, and a penetration strength P newtons (N)/20 μm of the porous layer and a percentage M of a mass of the inorganic particles in a total mass of the porous layer satisfy the following relational expression:
9
≤
P
M
+
1
≤
1
5
0
.
2 . The electrochemical device according to claim 1 , wherein the porous layer further comprises an initiator, and based on a total mass of the porous layer, a weight percent of the nanofibers is 4.9 wt % to 95 wt %, a weight percent of the inorganic particles is 4.9 wt % to 95 wt %, a weight percent of the crosslinker plus the initiator is 0.1 wt % to 40 wt %, and a mass of the initiator is 5% to 20% of a total mass of the crosslinker and the initiator.
3 . The electrochemical device according to claim 2 , wherein the initiator is selected from the group consisting of benzoyl peroxide, tert-butyl benzoyl peroxide, methyl ethyl ketone peroxide, azobisisobutyronitrile, azobisisoheptanenitrile, dimethyl azobisisobutyrate, azobisisobutylamidine hydrochloride, boron trifluoride, phosphorus pentafluoride, titanium tetrachloride, tin tetrachloride and zinc dichloride.
4 . The electrochemical device according to claim 2 , wherein each of the nanofibers comprises a core layer and a shell layer, and the crosslinker and the initiator are comprised in the shell layer.
5 . The electrochemical device according to claim 1 , wherein P≥16.
6 . The electrochemical device according to claim 1 , wherein P≥20.
7 . The electrochemical device according to claim 1 , wherein the crosslinker is selected from the group consisting of polyisocyanate, hexamethoxymethylmelamine, N-methylol acrylamide, carbodi-imide, trimethylolpropane, aziridine, dicumyl peroxide, butyl acrylate, N,N′-methylene bisacrylamide, 2,5-dimethyl-2,5-bis(tert-butylperoxide) hexane, bisphenol A epoxy resin, an acrylate derivative, a nitrile-containing polymer, styrene, vinyl fluoride, acrylonitrile, acrylamide, vinyl acetate, alkyl vinyl ether, alkylene oxide, and a trimethylene oxide derivative.
8 . The electrochemical device according to claim 1 , wherein the nanofibers comprise a flat ribbon fiber, and a ratio of a length value at a widest position to a length value at a narrowest position of a cross-section of the flat ribbon fiber is 2 to 100.
9 . The electrochemical device according to claim 8 , wherein the ratio of the length value at a widest position to the length value at a narrowest position of a cross-section of the flat ribbon fiber is 5 to 20.
10 . The electrochemical device according to claim 1 , wherein the nanofibers are selected from the group consisting of polyvinylidene difluoride, polyimide, polyamide, polyacrylonitrile, polyethylene glycol, polyethylene oxide, polyphenylene ether, polypropylene carbonate, polymethyl methacrylate, polyethylene terephthalate, polyvinylidene difluoride-hexafluoropropylene, polyvinylidene difluoride-chlorotrifluoroethylene, and a derivative thereof.
11 . The electrochemical device according to claim 1 , wherein the porous layer is characterized by at least one of the following:
an air permeability of the porous layer is 5 s/100 cm 3 to 400 s/100 cm 3 ;
a porosity of the porous layer is 30% to 95%;
an average pore diameter of the porous layer is 20 nm to 10 μm;
a thickness of the porous layer is 1 μm to 20 μm;
pore diameters of the porous layer decrease linearly in a thickness direction from a region farther away from the electrode plate to a region closer to the electrode plate;
the pore diameters of the porous layer decrease nonlinearly in the thickness direction from the region farther away from the electrode plate to the region closer to the electrode plate; or
the pore diameters of the porous layer decrease discontinuously in the thickness direction from the region farther away from the electrode plate to the region closer to the electrode plate.
12 . The electrochemical device according to claim 1 , wherein a number of the inorganic particles per unit area of the porous layer is 5×10 7 /m 2 to 3×10 19 /m 2 .
13 . The electrochemical device according to claim 1 , wherein a mass of the inorganic particles per unit area of the porous layer is 0.004 g/m 2 to 60 g/m 2 .
14 . The electrochemical device according to claim 1 , wherein an average particle diameter of the inorganic particles is 0.01 μm to 10 μm.
15 . The electrochemical device according to claim 1 , wherein the inorganic particles are selected from the group consisting of HfO 2 , SrTiO 3 , SnO 2 , CeO 2 , MgO, NiO, CaO, BaO, ZnO, ZrO 2 , Y 2 O 3 , Al 2 O 3 , TiO 2 , SiO 2 , boehmite, magnesium hydroxide, aluminum hydroxide, lithium phosphate, lithium titanium phosphate, lithium aluminum titanium phosphate, lithium lanthanum titanate, lithium germanium thiophosphate, lithium nitride, SiS 2 glass, P 2 S 5 glass, Li 2 O, LiF, LiOH, Li 2 CO 3 , LiAlO 2 , Li 2 O—Al 2 O 3 —SiO 2 —P 2 O 5 —TiO 2 —GeO 2 ceramic and garnet ceramic.
16 . The electrochemical device according to claim 1 , wherein the porous layer is prepared by air spinning, or centrifugal spinning.
17 . An electronic device, comprising an electrochemical device, wherein the electrochemical device comprises an electrode plate and a porous layer formed on a surface of the electrode plate, wherein the porous layer comprises nanofibers and inorganic particles, the nanofibers and the inorganic particles are bonded together by a crosslinker, and a penetration strength P newtons (N)/20 μm of the porous layer and a percentage M of a mass of the inorganic particles in a total mass of the porous layer satisfy the following relational expression:
9
≤
P
M
+
1
≤
1
5
0
.
18 . The electronic device according to claim 17 , wherein the porous layer further comprises an initiator, and based on a total mass of the porous layer, a weight percent of the nanofibers is 4.9 wt % to 95 wt %, a weight percent of the inorganic particles is 4.9 wt % to 95 wt %, a weight percent of the crosslinker plus the initiator is 0.1 wt % to 40 wt %, and a mass of the initiator is 5% to 20% of a total mass of the crosslinker and the initiator.