Battery pack sealing cover and preparation method therefor, and automobile

Abstract

A battery pack sealing cover and a preparation method therefor, and an automobile. The battery pack sealing cover comprises the following components in parts by weight: 33-68 parts of polypropylene, 0-22 parts of polyethylene, 0.008-1 part of a repellent, 24-32 parts of a flame retardant, and 10.4-19 parts of a functional additive.

Description

Battery pack sealing cover, preparation method thereof and automobile

[0001] The present application claims priority to Chinese Patent Application No. 202410838302.X, filed on June 25, 2024, the entire contents of which are incorporated herein by reference. TECHNICAL FIELD

[0002] The present disclosure belongs to the technical field of batteries, and in particular relates to a battery pack sealing cover, a preparation method thereof, and an automobile. BACKGROUND

[0003] With the popularity of electric vehicles, the safety and reliability of the battery pack in the electric vehicle become more and more important. Generally, the battery pack includes a power battery module, a thermal management system, a battery management system, a shell, and a battery pack sealing cover, and has the advantages of high energy density and wide working temperature range. SUMMARY

[0004] In view of the problem that the battery pack upper cover in the related art is bitten by mice and then water enters, causing the battery pack to leak electricity or short circuit and catch fire, the present disclosure provides a battery pack sealing cover, a preparation method thereof, and an automobile.

[0005] The technical solution adopted by the present disclosure to solve the above technical problem is as follows:

[0006] In one aspect, the present disclosure provides a battery pack sealing cover comprising the following weight components: polypropylene 33-68 parts, polyethylene 0-22 parts, repellent 0.008-1 part, flame retardant 24-32 parts, and functional additive 10.4-19 parts.

[0007] In some embodiments, the battery pack sealing cover comprises the following weight components: polypropylene 33-68 parts, polyethylene 14-22 parts, repellent 0.03-1 part, flame retardant 24-32 parts, and functional additive 10.4-19 parts.

[0008] In some embodiments, the repellent comprises one or more of a bittering agent, capsaicin, and an organic tin compound.

[0009] In some embodiments, the repellent is selected from a bittering agent, and the bittering agent comprises picric-S.

[0010] In some embodiments, the flame retardant comprises one or more of melamine hydrobromide, inorganic hypophosphite, decabromodiphenyl ethane, antimony trioxide, ammonium polyphosphate, pentaerythritol, piperazine pyrophosphate, brominated triazine, bisisocyanate, and cyanurate melamine.

[0011] In some embodiments, the flame retardant comprises the following weight components: decabromodiphenyl ethane 18-24 parts, and antimony trioxide 6-8 parts.

[0012] In some embodiments, the functional aid includes one or more of a filler, an antioxidant, a toughening agent, a stabilizer, and a colorant.

[0013] In some embodiments, the functional aid includes the following weight components: 15-18 parts of a filler, 0.2-1 part of an antioxidant, 0-1 part of a toughening agent, 0-1 part of a stabilizer, and 0.3-1 part of a colorant.

[0014] In some embodiments, the filler includes one or more of calcium carbonate, talcum powder, clay, mica powder, silicon dioxide, calcium sulfate, fly ash, red mud, wood powder, and cellulose.

[0015] The antioxidant includes one or more of antioxidant 1010, antioxidant 3114, antioxidant 330, antioxidant 1790, antioxidant TNPP, antioxidant 168, antioxidant 626.

[0016] The toughening agent includes one or more of styrene-butadiene-styrene block copolymer, hydrogenated styrene-butadiene-styrene block copolymer, ethylene-propylene-diene rubber, terpolymer ethylene-propylene-diene rubber, methyl methacrylate-butadiene-styrene copolymer, ethylene-octene copolymer, ethylene-acrylate copolymer.

[0017] The stabilizer includes at least one of titanium white or hydrotalcite.

[0018] The colorant includes one or more of carbon black, titanium white, and Hansa yellow.

[0019] In another aspect, the present disclosure also provides a method for preparing a battery pack sealing cover, the battery pack sealing cover being the battery pack sealing cover of any of the above embodiments. The paper cup method includes:

[0020] Mixing the polypropylene, polyethylene, repellent, flame retardant, and functional aid according to weight parts to obtain a first mixture;

[0021] Granulating and drying the first mixture to obtain a polyolefin composite material; and

[0022] Blister forming the polyolefin composite material to obtain a battery pack sealing cover.

[0023] In another aspect, the present disclosure also provides an automobile including a battery pack. The battery pack satisfies one of the following: the battery pack includes the battery pack sealing cover described above; or the battery pack includes the battery pack sealing cover prepared by the method for preparing a battery pack sealing cover described above.

[0024] In the present disclosure, by adding the repellent and the flame retardant in the battery pack sealing cover, the battery pack sealing cover has the characteristics of preventing animals from biting without affecting the flame retardation effect, further reducing the risk of water entering the battery pack after the battery pack sealing cover is bitten by animals, causing the battery pack to leak electricity or short circuit and catch fire.

[0025] Moreover, the effect of preventing animals from biting of the repellent is derived from the irritating smell it has itself. The weight of the repellent added in the battery pack sealing cover of some embodiments of the present disclosure is 0.008-1 parts, so that the battery pack sealing cover has no ecological toxicity, is non-carcinogenic, non-mutagenic or non-teratogenic, and meets the environmental protection standards of Restriction of Hazardous Substances (ROHS), Registration, Evaluation, Authorization and Restriction of Chemicals (REACH), and End-of-Life Vehicle (ELV). BRIEF DESCRIPTION OF DRAWINGS

[0026] FIG. 1 is a rat prevention test effect diagram of a battery pack sealing cover sample according to Embodiment 1, Embodiments 5-7 and Comparative Example 1 of the present disclosure;

[0027] FIG. 2 is a flowchart of a preparation method of a battery pack sealing cover according to some embodiments of the present disclosure;

[0028] FIG. 3 is a block diagram of an automobile according to some embodiments of the present disclosure. DETAILED DESCRIPTION

[0029] With the popularity of electric vehicles, the safety and reliability of battery packs become more and more important. When the battery pack is working, the overall temperature is relatively high, and sometimes it becomes a warm place for wild animals such as rats. Therefore, the sealing cover (such as the upper cover) of some battery packs becomes the object of biting by wild animals.

[0030] The battery pack sealing cover in the related art is usually made of polypropylene (PP) material. However, the PP material is soft and has low strength, and cannot prevent biting during long-term use of the battery pack. There is a risk that the upper cover of the battery pack will be bitten by wild animals and water will enter, causing the battery pack to leak electricity or short circuit and catch fire.

[0031] Therefore, it is an important requirement to develop a battery pack sealing cover material that prevents biting.

[0032] In order to make the technical problems, technical solutions and beneficial effects solved by the present disclosure clearer, the present disclosure will be further described in detail below in combination with embodiments. It should be understood that the embodiments described herein are only used to explain the present disclosure and not used to limit the present disclosure.

[0033] Some embodiments of the present disclosure provide a battery pack sealing cover comprising the following weight components: polypropylene 33-68 parts, polyethylene 0-22 parts, repellent 0.008-1 part, flame retardant 24-32 parts, and functional auxiliary agent 10.4-19 parts.

[0034] It can be understood that by adding repellent and flame retardant in the battery pack sealing cover, the battery pack sealing cover has the characteristics of preventing animal biting without affecting the flame retardation effect, further reducing the risk of water entering the battery pack after being bitten by animals, causing the battery pack to leak electricity or short circuit and fire.

[0035] Moreover, the effect of preventing animal biting of the repellent is derived from its irritating smell. In some embodiments of the present disclosure, the weight of the repellent added is 0.008-1 parts, so that the battery pack sealing cover has no ecological toxicity, is non-carcinogenic, non-mutagenic or non-teratogenic, and meets the ROHS, REACH and ELV environmental protection standards.

[0036] For example, the weight of the battery pack sealing cover is 100 parts, the polypropylene can be 33 parts, 36 parts, 39 parts, 43 parts, 46 parts, 49 parts, 52 parts, 55 parts, 58 parts, 61 parts, 64 parts or 68 parts; the polyethylene can be 0 parts, 3 parts, 6 parts, 9 parts, 12 parts, 15 parts, 18 parts or 21 parts, and by adding polyethylene, the toughness of the battery pack sealing cover can be improved; the repellent can be 0.008 parts, 0.01 parts, 0.03 parts, 0.05 parts, 0.08 parts, 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts or 1 part; the flame retardant can be 24 parts, 25 parts, 26 parts, 27 parts, 28 parts, 29 parts, 30 parts, 31 parts or 32 parts; and the functional auxiliary agent can be 10.4 parts, 11 parts, 12 parts, 13 parts, 14 parts, 15 parts, 16 parts, 17 parts, 18 parts or 19 parts.

[0037] In some embodiments, the battery pack sealing cover comprises the following weight components: polypropylene 33-68 parts, polyethylene 14-22 parts, repellent 0.03-1 part, flame retardant 24-32 parts, and functional auxiliary agent 10.4-19 parts. By adjusting the amount of repellent and polyethylene added, the cost performance can be improved on the premise of improving the mechanical properties and rat biting prevention effect of the battery pack sealing cover.

[0038] In some embodiments, the repellent includes one or more of a bittering agent, a capsaicin, and an organotin compound.

[0039] In some embodiments, the repellent is selected from a bittering agent, the bittering agent including picric-S. By adding a bittering agent, the irritating odor of the battery pack sealing cover can be reduced, and since the bittering agent is non-toxic and harmless, the environmental performance of the battery pack sealing cover can be improved.

[0040] In some embodiments, the flame retardant includes one or more of melamine hydrobromide, inorganic hypophosphite, decabromodiphenyl ethane, antimony trioxide, ammonium polyphosphate, pentaerythritol, piperazine pyrophosphate, brominated triazine, bircum, cyanurate melamine.

[0041] In some embodiments, the flame retardant includes the following weight components: decabromodiphenyl ethane 18-24 parts, antimony trioxide 6-8 parts. By compounding decabromodiphenyl ethane and antimony trioxide, the flame retardant effect of the battery pack sealing cover is ensured, and the environmental performance of the battery pack sealing cover is improved.

[0042] In some embodiments, the functional aid includes one or more of a filler, an antioxidant, a toughening agent, a stabilizer, and a colorant.

[0043] It can be understood that by adding a filler, the heat resistance of the battery pack sealing cover can be improved, and at the same time the wear resistance and dimensional stability of the plastic product are improved. By adding an antioxidant, the antioxidant effect of the battery pack sealing cover can be improved. By adding a toughening agent, the mechanical properties of the battery pack sealing cover can be improved. By adding a stabilizer, the thermal stability and light stability of the battery pack sealing cover can be improved. By adding a colorant, the battery pack sealing cover can be colored to improve its ornamental value.

[0044] In some embodiments, the functional aid includes the following weight components: filler 15-18 parts, antioxidant 0.2-1 part, toughening agent 0-1 part, stabilizer 0-1 part, and colorant 0.3-1 part.

[0045] In some embodiments, the filler includes one or more of calcium carbonate, talc, clay, mica powder, silicon dioxide, calcium sulfate, fly ash, red mud, wood powder, and cellulose.

[0046] The antioxidant includes one or more of antioxidant 1010, antioxidant 3114, antioxidant 330, antioxidant 1790, antioxidant TNPP (Tri(nonylphenyl) phosphite), antioxidant 168, antioxidant 626.

[0047] The toughening agent comprises one or more of styrene-butadiene-styrene block copolymer, hydrogenated styrene-butadiene-styrene block copolymer, ethylene-propylene-diene rubber, methacrylate-butadiene-styrene copolymer, ethylene-octene copolymer, and ethylene-acrylate copolymer.

[0048] The stabilizer comprises at least one of titanium white or hydrotalcite.

[0049] The colorant comprises one or more of carbon black, titanium white, and Hansa yellow.

[0050] In some embodiments, the filler is selected from talcum powder, the antioxidant is selected from antioxidant 1010, the toughening agent is selected from ethylene-octene copolymer, the stabilizer is selected from titanium white, and the colorant is selected from carbon black.

[0051] As shown in FIG. 2, some embodiments of the present disclosure further provide a preparation method of the battery pack sealing cover as described in any of the above embodiments, comprising the following steps S1 to S3.

[0052] In step S1, the polypropylene, polyethylene, repellent, flame retardant, and functional auxiliary agent are mixed according to weight parts to obtain a first mixture.

[0053] In step S2, the first mixture is granulated and dried to obtain a polyolefin composite material.

[0054] For example, the first mixture is put into a twin-screw extruder for extrusion granulation.

[0055] In step S3, the polyolefin composite material is blister molded to obtain the battery pack sealing cover.

[0056] In some embodiments, the process parameters of the twin-screw extruder include that the extrusion temperature is controlled at 180-230°C, and the screw rotation speed is controlled at 200-300 r / min.

[0057] As shown in FIG. 3, some embodiments of the present disclosure further provide an automobile 1000 comprising a battery pack 200. In some embodiments, the battery pack 200 comprises the battery pack sealing cover 100 as described in any of the above embodiments. In some embodiments, the battery pack 200 comprises the battery pack sealing cover 100 prepared by the preparation method of the battery pack sealing cover as described in any of the above embodiments.

[0058] The present disclosure is further illustrated by the following examples.

[0059] In some embodiments, the preparation method of the battery pack sealing cover comprises the following operation steps:

[0060] The polypropylene, polyethylene, decabromodiphenyl ethane, antimony trioxide, kerosene-S, talcum powder, antioxidant 1010, toughening agent POE (ethylene-octene copolymer, Polyolefin Elastomer), stabilizer titanium white powder, colorant carbon black are weighed by weight parts, uniformly mixed, and then put into a double screw extruder. The double screw extruder temperature parameters are set as 170℃, 180℃, 190℃, 190℃, 210℃, 210℃, 190℃, 180℃, respectively. The head temperature is about 175℃, and the screw rotation speed is about 240r / min. The polyolefin composite material is cooled, air dried, cut, screened, homogenized, and then extruded, blistered to obtain a battery pack sealing cover.

[0061] Examples 1-10

[0062] Examples 1-10 use the preparation method of the battery pack sealing cover as described above, including most of the operation steps in the above examples. The difference between Examples 1-10 is that the formula in Table 1 is used.

[0063] Comparative Examples 1-4

[0064] Comparative Examples 1-4 use the preparation method of the battery pack sealing cover as described above, including most of the operation steps in the above examples. The difference between Comparative Examples 1-4 is that the formula in Table 1 is used.

[0065] Table 1

[0066] Performance test

[0067] In the following, the battery pack sealing cover samples prepared by the above Examples 1-10 and Comparative Examples 1-4 will be tested for odor grade, protection rate, mechanical forming, and environmental performance.

[0068] Odor grade test

[0069] Referring to the QBYDQ-A1901.404-2018 standard, the thickness of the experimental sample in Table 2 is ≥3mm. The experimental container does not need to be added with water. The experimental container should be tightly covered and placed in a preheated electric heating constant temperature air drying oven and heated to (80±2)℃ and continued for 120±10min. After taking the experimental container out of the oven, it is cooled back to (60±5)℃, and then evaluated; the sampling is as shown in Table 2.

[0070] Table 2 Sampling method, sampling amount and selection of experimental container

[0071] Evaluation: The nose is placed close to the edge of the open container, with the edge of the container between the nose and the lips, the evaluator's nose is about 2-3 cm from the mouth of the container, the container cap is opened, the opening time should not exceed 10 seconds, the evaluator inhales normally (i.e. smells not fast or slow), the evaluation is carried out by at least three people, if the evaluation results of each evaluator differ by more than two levels or the evaluation results of the evaluators simultaneously appear ≤ 3 levels and ≥ 4 levels, at least five evaluators are required to repeat the test, a maximum of three appraisers are allowed to evaluate each test container, if there are five evaluators, two identical test samples need to be prepared; the evaluation results are described by the arithmetic mean of the evaluation results of each evaluator to describe the odor characteristics.

[0072] The odor evaluation standard is divided into 1-6 levels, and if there is a situation between two evaluation levels, a half-level evaluation is allowed.

[0073] The evaluation criteria are as follows:

[0074] 1st level: no odor;

[0075] 2nd level: slight odor, but no disturbing odor;

[0076] 3rd level: obvious odor, but no disturbing odor;

[0077] 4th level: disturbing odor;

[0078] 5th level: strong disturbing odor;

[0079] 6th level: unbearable odor;

[0080] Protection rate test

[0081] According to the test standard of the People's Republic of China machinery industry standard JBT10696.10-2011 "Wire and cable mechanical and physical and chemical performance test method part 10: rat bite test", the determination standard is shown in table 3: the protection rate of the tested sample during the test is ≥0.9, which is considered to pass the test.

[0082] Table 3

[0083] Mechanical formation test

[0084] Test according to the test standards of ISO527-1:2012, ISO180:2013 and ISO179:2013.

[0085] Environmental performance test

[0086] According to the test standards of ROHS, REACH and ELV, the test results are shown in Table 4.

[0087] Table 4

[0088] As shown in Figure 1 and in combination with the test results in Table 4, the greater the amount of bittering agent added, the greater the odor grade of the battery pack sealing cover, and the better the rat-proof effect. As shown in the test results of Example 1 and Comparative Example 1, the rat-proof effect can be observed by adding bittering agent. As shown in the test results of Example 7, when the addition ratio is 0.03%, the battery pack sealing cover has the highest cost performance.

[0089] However, as shown in the test results of Example 1, Comparative Example 2 and Comparative Example 3, when the amount of bittering agent-S added is 1.5% (Comparative Example 2), the protection rate of the battery pack sealing cover is not significantly different from that of the battery pack sealing cover in Example 9. When the amount of bittering agent-S added is 0.005% (Comparative Example 3), the protection rate of the battery pack sealing cover cannot meet the rat-proof requirement. Therefore, when the amount of bittering agent-S added is 0.008%-1%, the rat-proof effect of the battery pack sealing cover can be ensured, and the mechanical properties of the battery pack sealing cover are not affected.

[0090] As shown in the test results of Examples 1-3 and Comparative Example 4, when the content of polypropylene is outside the range of 33%-68% and the content of polyethylene is higher than 22%, the impact strength of the battery pack sealing cover is enhanced, but the tensile strength and the bending strength are significantly reduced. Therefore, when the content of polypropylene is within the range of 33%-68% and the content of polyethylene is within the range of 0-22%, the mechanical properties of the battery pack sealing cover can meet the requirements.

[0091] As shown in the test results of Example 1 and Comparative Example 1, the mechanical properties and environmental performance of the battery pack sealing cover after adding the repellent meet the requirements.

[0092] The above description is only the preferred embodiment of the present disclosure, and is not intended to limit the present disclosure. Any modification, equivalent replacement and improvement made within the spirit and principle of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. A battery pack sealing cover, comprising the following components by weight: 33-68 parts of polypropylene, 0-22 parts of polyethylene, 0.008-1 parts of repellent, 24-32 parts of flame retardant, and 10.4-19 parts of functional additives.

2. The battery pack sealing cover according to claim 1 comprises the following components by weight: 33-68 parts of polypropylene, 14-22 parts of polyethylene, 0.03-1 part of repellent, 24-32 parts of flame retardant, and 10.4-19 parts of functional additives.

3. The battery pack sealing cover according to claim 1 or 2, wherein, The repellent includes one or more of bittering agents, capsaicin, and organotin compounds.

4. The battery pack sealing cover according to claim 3, wherein, The repellent agent includes a bittering agent, and the bittering agent includes bittern-S.

5. The battery pack sealing cover according to any one of claims 1 to 4, wherein, The flame retardant includes one or more of the following: melamine hydrobromide, inorganic hypophosphite, decabromodiphenyl ethane, antimony trioxide, ammonium polyphosphate, pentaerythritol, piperazine pyrophosphate, bromotriazine, benzo[a]benzyl cyanurate, and melamine hydrochloride.

6. The battery pack sealing cover according to claim 5, wherein, The flame retardant comprises the following components by weight: 18-24 parts of decabromodiphenyl ethane and 6-8 parts of antimony trioxide.

7. The battery pack sealing cover according to any one of claims 1 to 6, wherein, The functional additives include one or more of fillers, antioxidants, toughening agents, stabilizers, and colorants.

8. The battery pack sealing cover according to claim 7, wherein, The functional additives comprise the following components by weight: 15-18 parts filler, 0.2-1 parts antioxidant, 0-1 parts toughening agent, 0-1 parts stabilizer, and 0.3-1 parts colorant.

9. The battery pack sealing cover according to claim 7 or 8, wherein, The filler includes one or more of the following: calcium carbonate, talc, clay, mica powder, silica, calcium sulfate, fly ash, red mud, wood flour, and cellulose. The antioxidants include one or more of antioxidants 1010, 3114, 330, 1790, TNPP, 168, and 626. The toughening agent includes one or more of the following: styrene-butadiene-styrene block copolymer, hydrogenated styrene-butadiene-styrene block copolymer, ethylene propylene diene monomer (EPDM) rubber, ethylene propylene diene monomer (EPDM) rubber, methyl methacrylate-butadiene-styrene copolymer, ethylene-octene copolymer, and ethylene-acrylate copolymer. The stabilizer includes at least one of titanium dioxide or hydrotalcite; The colorant includes one or more of carbon black, titanium dioxide, and Hansa yellow.

10. A method for preparing a battery pack sealing cover, wherein, The battery pack sealing cover is the battery pack sealing cover according to any one of claims 1-9; the preparation method includes: The polypropylene, the polyethylene, the repellent, the flame retardant, and the functional additives are mixed in parts by weight to obtain a first mixture; The first mixture is granulated and dried to obtain a polyolefin composite material; and The battery pack sealing cover is obtained by vacuum forming the polyolefin composite material.

11. A vehicle comprising a battery pack; wherein, The battery pack satisfies one of the following: The battery pack includes a battery pack sealing cover according to any one of claims 1-9; or The battery pack includes the battery pack sealing cover prepared by the method for preparing the battery pack sealing cover according to claim 10.

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