阅读说明：本技术 一种电力储能系统用低烟无卤阻燃电池连接电缆 (Low-smoke halogen-free flame-retardant battery connecting cable for power energy storage system ) 是由 汪关才 李成成 刘亚农 于 2021-08-04 设计创作，主要内容包括：本发明公开了一种电力储能系统用低烟无卤阻燃电池连接电缆,包括缆芯、绝缘层、阻水层、阻燃层和护套层；缆芯为铜芯或镀锡铜芯,绝缘层为硅橡胶绝缘层或交联聚乙烯绝缘层,阻水层为聚酯纤维阻水带,阻燃层为无卤玻璃纤维带或耐火云母带；外护套包括如下组分：第一基体树脂50～80份、第二基体树脂10～30份、相容剂5～15份、阻燃剂20～50份、协效阻燃剂5～10份、表面改性剂0.5～1份、助交联剂4～8份、抗氧剂0.2～1份和润滑剂0.2～1份；第一基体树脂选自EVA、PE、POE中的一种或多种；第二基体树脂由所述聚醚型聚氨酯弹性体和聚对苯二甲酸丁二醇酯组成,其质量比为1～2:1～2。本发明的电池连接电缆,具有柔韧性高、弹性好、阻燃性好的优点,且可以在-40℃-125℃的环境下长期使用。(The invention discloses a low-smoke halogen-free flame-retardant battery connecting cable for a power energy storage system, which comprises a cable core, an insulating layer, a water-blocking layer, a flame-retardant layer and a sheath layer, wherein the insulating layer is arranged on the cable core; the cable core is a copper core or a tinned copper core, the insulating layer is a silicon rubber insulating layer or a crosslinked polyethylene insulating layer, the water-blocking layer is a polyester fiber water-blocking tape, and the flame-retardant layer is a halogen-free glass fiber tape or a fire-resistant mica tape; the outer sheath comprises the following components: 50-80 parts of first matrix resin, 10-30 parts of second matrix resin, 5-15 parts of compatilizer, 20-50 parts of flame retardant, 5-10 parts of synergistic flame retardant, 0.5-1 part of surface modifier, 4-8 parts of auxiliary crosslinking agent, 0.2-1 part of antioxidant and 0.2-1 part of lubricant; the first matrix resin is selected from one or more of EVA, PE and POE; the second matrix resin is composed of the polyether polyurethane elastomer and polybutylene terephthalate, and the mass ratio of the polyether polyurethane elastomer to the polybutylene terephthalate is 1-2: 1-2. The battery connecting cable has the advantages of high flexibility, good elasticity and good flame retardance, and can be used for a long time in the environment of minus 40-125 ℃.)

1. A low-smoke halogen-free flame-retardant battery connecting cable for a power energy storage system comprises a cable core, wherein an insulating layer, a water blocking layer and a flame-retardant layer are sequentially wound on the outer side of the cable core, and a sheath layer is arranged on the outer side of the flame-retardant layer; it is characterized in that the preparation method is characterized in that,

the cable core is a copper core or a tinned copper core, the insulating layer is a silicone rubber insulating layer or a crosslinked polyethylene insulating layer, the water-blocking layer is a polyester fiber water-blocking tape, and the flame-retardant layer is a halogen-free glass fiber tape or a fire-resistant mica tape;

the outer sheath is prepared from a halogen-free cross-linked flame-retardant sheath material, and the halogen-free cross-linked flame-retardant sheath material comprises the following components in parts by weight: 50-80 parts of first matrix resin, 10-30 parts of second matrix resin, 5-15 parts of compatilizer, 20-50 parts of flame retardant, 5-10 parts of synergistic flame retardant, 0.5-1 part of surface modifier, 4-8 parts of auxiliary crosslinking agent, 0.2-1 part of antioxidant and 0.2-1 part of lubricant;

wherein the first matrix resin is selected from one or more of EVA, PE and POE; the second matrix resin is composed of the polyether polyurethane elastomer and polybutylene terephthalate, and the mass ratio of the polyether polyurethane elastomer to the polybutylene terephthalate is 1-2: 1-2.

2. The low-smoke halogen-free flame-retardant battery connecting cable for the power energy storage system according to claim 1, characterized in that a protective layer with a thickness of 10-50 μm is coated on the surface of the cable core, and the protective layer is a polyetherimide protective layer or a polyetheretherketone protective layer.

3. The low-smoke halogen-free flame-retardant battery connecting cable for the power energy storage system as claimed in claim 1, wherein the thickness of the insulating layer is 1-3 mm, the thickness of the water-blocking layer is 50-200 μm, and the thickness of the flame-retardant layer is 100-300 μm.

4. The low-smoke zero-halogen flame-retardant battery connecting cable for the power energy storage system as claimed in claim 1, wherein the compatibilizer is maleic anhydride grafted styrene copolymer.

5. The low-smoke halogen-free flame-retardant battery connecting cable for the power energy storage system according to claim 1, characterized in that the flame retardant is composed of an inorganic hydroxide flame retardant and a polyphosphate flame retardant, and the mass ratio of the inorganic hydroxide flame retardant to the polyphosphate flame retardant is 2-5: 1.

6. The low-smoke zero-halogen flame-retardant battery connecting cable for the power energy storage system as claimed in claim 1, wherein the flame-retardant synergist is selected from one or more of polysiloxane, nano-layered silicate and fibrous wollastonite.

7. The low-smoke halogen-free flame-retardant battery connecting cable for the power energy storage system according to claim 1, wherein the surface modifier is one or more selected from vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (beta-methoxyethoxy) silane and linear polydimethylsiloxane; the lubricant is selected from one or more of calcium stearate, zinc stearate, polyethylene wax and tetra [ beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid ] pentaerythritol ester.

8. The low-smoke halogen-free flame-retardant battery connecting cable for the power energy storage system according to claim 1, wherein the antioxidant is a compound antioxidant formed by compounding a hindered amine antioxidant and any one selected from zinc oxide, titanium dioxide and fumed silica.

9. The low-smoke zero-halogen flame-retardant battery connecting cable for the power energy storage system according to claim 1, wherein the auxiliary crosslinking agent is selected from one or more of triallyl isocyanurate, triallyl cyanurate, and trimethylolpropane trimethacrylate.

10. The low-smoke halogen-free flame-retardant battery connecting cable for the power energy storage system according to any one of claims 1 to 9, wherein the preparation method of the halogen-free crosslinked flame-retardant sheathing compound comprises the following steps:

adding the flame retardant, the synergistic flame retardant and the surface modifier into a mixer at the temperature of 60-90 ℃, and mixing for 10-30 min at the rotating speed of 200-500 rpm;

respectively adding a first matrix resin, a second matrix resin, a compatilizer, an auxiliary cross-linking agent, an antioxidant and a lubricant into the mixer at the temperature of 90-120 ℃, and mixing at the rotating speed of 500-1000 rpm for 30-60 min to obtain a mixture;

and discharging the mixture from the mixer, adding the mixture into a double-screw extruder, extruding, granulating and cooling at the temperature of 220-260 ℃ to obtain the halogen-free cross-linked flame-retardant sheathing compound.

Technical Field

The invention relates to the technical field of cables, in particular to a low-smoke halogen-free flame-retardant battery connecting cable for a power energy storage system.

Background

Because the energy sources needed by people are very temporal and spatial, in order to reasonably utilize the energy sources and improve the utilization rate of the energy, a device is needed to collect and store the redundant energy which is not used temporarily in a period of time into an Energy Storage System (ESS) in a certain mode, and then the redundant energy is extracted and used at the peak time or is transported to a place where the energy is in short supply for reuse. With the gradual maturity and scale of new energy such as photovoltaic energy, wind power energy, nuclear energy and the like, the development of energy storage is the key point for solving the high permeability of renewable clean energy. The links of power generation, power transmission, power distribution and power utilization of the power system can embody the value of energy storage.

The energy storage cable is a commonly used cable in an electric energy storage system, and generally refers to a connecting cable between batteries in the battery energy storage system, between battery packs, between a battery pack and a junction box or a converter. The cable is applied to direct current systems with rated voltages of DC600V, DC1000V and DC1500V, and the highest temperature resistant grade is 125 ℃. In view of the special use environment of the energy storage cable, strict requirements are provided for the cable in the aspects of thermal life, high and low temperature resistance, acid and alkali resistance, battery acid resistance, salt mist resistance, UV resistance, low smoke, zero halogen, combustion performance and the like. The temperature range of the using environment of the cable is-40 ℃ to +90 ℃, and the cable can be applied to three using scenes, namely indoor, outdoor movement and outdoor.

The cable insulation material and the sheath material in the current battery connecting cable mainly comprise: -40 ℃ to 90 ℃ grades of materials such as: PVC material, TPE material, cross-linked elastomer (EPDM or CPE) and cross-linked polyolefin material (XLPO); -40 ℃ to 125 ℃ grades of materials such as: cross-linked polyolefin material (XLPO), silicone rubber material.

The manner in which the battery connecting cable is routed places high demands on the flexibility of the overall cable, while a balance between flexibility, high elasticity and flame retardancy is required. In addition, because the energy storage device is in operation for a long period of time, it will be a major challenge to the service life of the cable material. Therefore, it is necessary to develop a material for energy storage cables, which has high flexibility, good elasticity, good flame retardancy and long service life.

Disclosure of Invention

The invention aims to solve the technical problem of providing a low-smoke halogen-free flame-retardant battery connecting cable for a power energy storage system, which has the advantages of high flexibility, good elasticity and good flame retardance, can be used for a long time in an environment of-40-125 ℃, and has long service life.

In order to solve the technical problems, the invention provides the following technical scheme:

the invention provides a low-smoke halogen-free flame-retardant battery connecting cable for a power energy storage system, which comprises a cable core, wherein an insulating layer, a water-blocking layer and a flame-retardant layer are sequentially wound on the outer side of the cable core, and a sheath layer is arranged on the outer side of the flame-retardant layer;

the cable core is a copper core or a tinned copper core, the insulating layer is a silicone rubber insulating layer or a crosslinked polyethylene insulating layer, the water-blocking layer is a polyester fiber water-blocking tape, and the flame-retardant layer is a halogen-free glass fiber tape or a fire-resistant mica tape;

the outer sheath is prepared from a halogen-free cross-linked flame-retardant sheath material, and the halogen-free cross-linked flame-retardant sheath material comprises the following components in parts by weight: 50-80 parts of first matrix resin, 10-30 parts of second matrix resin, 5-15 parts of compatilizer, 20-50 parts of flame retardant, 5-10 parts of synergistic flame retardant, 0.5-1 part of surface modifier, 4-8 parts of auxiliary crosslinking agent, 0.2-1 part of antioxidant and 0.2-1 part of lubricant;

wherein the first matrix resin is selected from one or more of EVA, PE and POE; the second matrix resin is composed of the polyether polyurethane elastomer and polybutylene terephthalate (PBT), and the mass ratio of the polyether polyurethane elastomer to the polybutylene terephthalate (PBT) is 1-2: 1-2.

Further, a protective layer with the thickness of 10-50 mu m is coated on the surface of the cable core, and the protective layer is a polyetherimide protective layer or a polyether-ether-ketone protective layer. The polyetherimide and the polyether-ether-ketone have excellent high temperature resistance and flame retardance, and cable cores can be well protected; meanwhile, the cable core has excellent electrical insulation and can improve the insulation performance of the cable core by matching with the insulation layer.

Further, the thickness of the insulating layer is 1-3 mm, the thickness of the water-resistant layer is 50-200 mu m, and the thickness of the flame-retardant layer is 100-300 mu m.

Further, the compatilizer is a maleic anhydride grafted styrene copolymer, and the compatilizer can improve the compatibility of the PBT and the first matrix resin.

Further, the flame retardant is composed of an inorganic hydroxide flame retardant and a polyphosphate flame retardant, and the mass ratio of the inorganic hydroxide flame retardant to the polyphosphate flame retardant is 2-5: 1. Wherein, the inorganic hydroxide flame retardant comprises but is not limited to aluminum hydroxide and magnesium hydroxide, and the polyphosphate flame retardant comprises but is not limited to ammonium polyphosphate and pentaerythritol ammonium polyphosphate. According to the invention, the inorganic flame retardant and the organic flame retardant are compounded for use, so that the advantages of the inorganic flame retardant and the organic flame retardant are fully combined, and a better flame retardant effect can be achieved.

Further, the flame retardant synergist is selected from one or more of polysiloxane, nano layered silicate and fibrous wollastonite. Wherein, the polysiloxane comprises organopolysiloxane with alkyl, substituted alkyl and phenyl at side chain, such as polydimethylsiloxane, and the nano layered silicate comprises but is not limited to nano montmorillonite and nano kaolin. Polysiloxane has low surface energy, so that it is easy to migrate from the inside of polymer to the surface during combustion, and quickly gathers into carbon, so that it can isolate oxygen and raise fire-retarding effect. And the nano layered silicate and the fibrous wollastonite can also promote the formation of a stable carbon layer, so that the flame retardant effect is improved. And secondly, the use amount of the main flame retardant can be remarkably reduced through the use of the flame retardant synergist, so that the influence of the large use amount of the main flame retardant on the flexibility and the mechanical property of the cable is reduced. In addition, the sheet-shaped silicate and the fibrous wollastonite can also be used as a toughening agent of a resin matrix, so that the mechanical property and the aging resistance of the cable are improved.

Further, the surface modifier is selected from one or more of vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (beta-methoxyethoxy) silane and linear polydimethylsiloxane.

Further, the antioxidant is a compound antioxidant formed by compounding a hindered amine antioxidant and any one of zinc oxide, titanium dioxide and fumed silica. Compared with a single antioxidant, the compound antioxidant has better antioxidant effect, and particularly, after the fumed silica is added into a resin matrix, the strength and toughness of the material can be improved.

Further, the lubricant is selected from one or more of calcium stearate, zinc stearate, polyethylene wax and pentaerythritol tetrakis [ beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate ].

Further, the auxiliary crosslinking agent is selected from one or more of triallyl isocyanurate (TAIC), triallyl cyanurate (TAC) and trimethylolpropane trimethacrylate (TMPTMA).

The preparation method of the halogen-free cross-linked flame-retardant sheath material comprises the following steps:

adding the flame retardant, the synergistic flame retardant and the surface modifier into a mixer at the temperature of 60-90 ℃, and mixing for 10-30 min at the rotating speed of 200-500 rpm;

respectively adding a first matrix resin, a second matrix resin, a compatilizer, an auxiliary cross-linking agent, an antioxidant and a lubricant into the mixer at the temperature of 90-120 ℃, and mixing at the rotating speed of 500-1000 rpm for 30-60 min to obtain a mixture;

and discharging the mixture from the mixer, adding the mixture into a double-screw extruder, extruding, granulating and cooling at the temperature of 220-260 ℃ to obtain the halogen-free cross-linked flame-retardant sheathing compound.

According to the invention, the raw materials are distributed and mixed, so that the modification effect of the surface modifier on the flame retardant and the synergistic flame retardant can be improved, and the compatibility of the flame retardant and the synergistic flame retardant with the resin base material can be improved; in addition, the resin raw materials are mixed at a high rotating speed at a high temperature, and the surface of the resin material is in a micro-melting state and a high surface energy state, so that bonding reaction can be performed between the resin material and the filler, and better mixing and modifying effects are realized.

And after the cable is prepared by the sheath material subsequently, crosslinking is carried out by adopting an irradiation mode.

Compared with the prior art, the invention has the beneficial effects that:

1. in order to improve the flexibility and high and low temperature resistance of the cable material, at least one of EVA, PE and POE is selected to be compounded with the polyether polyurethane elastomer and the polybutylene terephthalate according to a specific proportion, and then a certain proportion of the flame retardant, the synergistic flame retardant, the surface modifier, the auxiliary crosslinking agent, the antioxidant and the lubricant are added for composite modification, so that the obtained halogen-free crosslinking flame-retardant sheath material has excellent comprehensive performance, the tensile strength of the cable material exceeds 23MPa, the elongation at break of the cable material exceeds 380%, the Shore hardness of the cable material is lower than 75, the oxygen index of the cable material exceeds 33, the finished cable prepared from the halogen-free crosslinking flame-retardant sheath material does not crack after being wound for 240 hours at minus 40 ℃, and the tensile strength retention and the elongation at break retention rate are both higher than 96% after being treated for 240 hours at 158 ℃. The cable can be used for a long time in the environment of-40 ℃ to 125 ℃, has long service life, and can meet various requirements of a power energy storage system on the cable.

2. According to the low-smoke halogen-free flame-retardant battery connecting cable for the power energy storage system, the surface of the cable core is coated with the polyetherimide coating or the polyether-ether-ketone coating with the thickness of 10-50 mu m, the polyetherimide and the polyether-ether-ketone have excellent insulativity and flame retardance, and the polyetherimide and the polyether-ether-ketone are mainly used as high-temperature-resistant protective materials besides insulating protective materials of conductors, so that the cable core is well protected.

3. According to the invention, the polybutylene terephthalate is introduced into the sheath material formula, so that the polybutylene terephthalate has excellent heat resistance, the long-term use temperature can reach 150 ℃, and the high-temperature resistance of the matrix resin can be obviously improved; and the polybutylene terephthalate also has good toughness and good char forming property, and is beneficial to improving the flexibility and the flame retardant capability of the matrix resin.

4. The polyether polyurethane elastomer is also introduced into the sheath material formula, has good low-temperature flexibility, and can improve the low-temperature toughness of EVA, PE or POE; the polyether polyurethane elastomer has low viscosity, and can improve the processing performance of the resin material; in addition, the polyether polyurethane elastomer has good hydrolysis resistance, can be used for a long time, and is beneficial to prolonging the service life of the cable. By controlling the mass ratio of the polyether polyurethane elastomer to the polybutylene terephthalate to be 1-2: 1-2, the high temperature resistance and the low temperature resistance of the sheath material can be balanced, so that the sheath material has good high temperature resistance and low temperature resistance.

5. According to the low-smoke halogen-free flame-retardant battery connecting cable for the power energy storage system, the flame-retardant layer made of the halogen-free glass fiber tape or the fire-resistant mica tape is arranged in the sheath layer, so that the flame-retardant requirement on the sheath layer is reduced, the addition amount of the flame retardant in the sheath material can be reduced, and the influence of the large amount of the flame-retardant filler on the flexibility of the sheath material is avoided.

Drawings

Fig. 1 is a schematic sectional view showing a battery connecting cable according to embodiment 1 of the present invention;

wherein: 1. a cable core; 2. a protective layer; 3. an insulating layer; 4. a water resistant layer; 5. a flame retardant layer; 6. a sheath layer.

Detailed Description

The present invention is further described below in conjunction with the following figures and specific examples so that those skilled in the art may better understand the present invention and practice it, but the examples are not intended to limit the present invention.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

The experimental methods used in the following examples are conventional methods unless otherwise specified, and materials, reagents and the like used therein are commercially available without otherwise specified.

Example 1

As shown in fig. 1, the embodiment provides a low-smoke halogen-free flame-retardant battery connection cable for an electric power energy storage system, which includes a cable core 1, and an insulating layer 3, a water blocking layer 4, a flame-retardant layer 5 and a sheath layer 6 which are sequentially arranged outside the cable core 1, wherein the cable core 1 is a tin-plated copper core, a polyether-ether-ketone protective layer 2 with a thickness of 30 μm is coated on the surface of the cable core, and the insulating layer 3 is an XLPO insulating layer with a thickness of 1 mm; the water-resistant layer 4 is formed by wrapping a polyester fiber water-resistant tape on the outer side of the insulating layer 3, and the thickness of the water-resistant tape is 200 mu m; the flame-retardant layer 5 is formed by wrapping a fire-resistant mica tape on the outer side of the waterproof layer 4, and the thickness of the flame-retardant layer is 200 mu m.

The sheath layer is prepared from a halogen-free cross-linked flame-retardant sheath material, and the halogen-free cross-linked flame-retardant sheath material comprises the following components in parts by weight: 60 parts of PE resin, 10 parts of polyether polyurethane elastomer, 10 parts of PBT resin, 5 parts of maleic anhydride grafted styrene copolymer, 30 parts of aluminum hydroxide, 10 parts of pentaerythritol ammonium polyphosphate, 5 parts of fibrous wollastonite, 1 part of vinyl trimethoxy silane, 4 parts of TAIC, 0.5 part of hindered amine antioxidant, 0.5 part of zinc oxide and 0.2 part of calcium stearate.

The preparation method of the halogen-free cross-linked flame-retardant sheath material comprises the following steps:

adding aluminum hydroxide, pentaerythritol ammonium polyphosphate, fibrous wollastonite and vinyl trimethoxy silane into a mixer, and mixing for 20min at 80 ℃ and 300 rpm; and then adding PE resin, polyether polyurethane elastomer, PBT resin, maleic anhydride grafted styrene copolymer, TAIC, hindered amine antioxidant, zinc oxide and calcium stearate into a mixer, and mixing for 60min at the temperature of 120 ℃ and the rotating speed of 800rpm to obtain a mixture. And discharging the mixture from the mixer, adding the mixture into a double-screw extruder, extruding, granulating and cooling at 250 ℃ to obtain the halogen-free cross-linked flame-retardant sheath material.

Examples 2 to 6, comparative examples 1 to 8

The formulations of the halogen-free cross-linked flame retardant sheathing compounds of examples 1 to 6 and comparative examples 1 to 8 are shown in tables 1 and 2, respectively.

TABLE 1 formulation of halogen-free crosslinked flame retardant sheathing compounds of examples 1-6

Table 2 formula of halogen-free cross-linked flame-retardant sheath material for comparative examples 1 to 8

In the above examples, the EVA had a VA content of 28% and a melt index of 3.0 to 3.5g/10min at 190 ℃ under 2.16 kg.

According to the same method as the examples, the components in the formula are prepared into the halogen-free cross-linking flame-retardant sheath material.

Performance detection

The halogen-free crosslinked flame-retardant sheathing materials or cables of examples 1 to 6 and comparative examples 1 to 8 were subjected to performance tests with reference to standard CQC 1143& PPP 58049A "Battery connection Cable for Power energy storage System", and the results are shown in tables 3 to 4.

Table 3 performance test results of the halogen-free cross-linked flame retardant sheathing materials and cables of examples 1 to 6

Table 4 results of performance test of the halogen-free cross-linked flame-retardant sheath materials and cables of comparative examples 1 to 8

From the results of the above table, it can be seen that compared with the comparative example, the halogen-free crosslinked flame retardant sheathing compound of the present invention is superior to the comparative example in various indexes, and particularly, after the treatment of 158 ℃ for 240 hours, the tensile strength retention rate and the elongation at break retention rate are significantly superior to the comparative example.

In conclusion, the cable disclosed by the invention has good low-temperature flexibility, the winding is not cracked after being processed at the temperature of minus 40 ℃ for 240 hours, and the tensile strength retention and the elongation at break retention are both more than 96% after being processed at the temperature of 158 ℃ for 240 hours.

The above-mentioned embodiments are merely preferred embodiments for fully illustrating the present invention, and the scope of the present invention is not limited thereto. The equivalent substitution or change made by the technical personnel in the technical field on the basis of the invention is all within the protection scope of the invention. The protection scope of the invention is subject to the claims.