KR102261946B1 - Composite type magnetic material for chargement of electric vehicle, wireless power receiving pad assembly comprising the same and the electric vehicle comprising thereof - Google Patents

Abstract

The present invention relates to a composite magnetic composite for charging an electric vehicle, comprising magnetic powders bonded to each other by a polymer resin, having excellent physical properties and sufficient impact resistance to be applied to automobiles at the same time, and an electric vehicle including the same. According to the present invention, it is useful to provide a composite magnetic composite having excellent impact resistance suitable for wireless charging of an electric vehicle and an electric vehicle including the same.

Description

COMPOSITE TYPE MAGNETIC MATERIAL FOR CHARGEMENT OF ELECTRIC VEHICLE, WIRELESS POWER RECEIVING PAD ASSEMBLY COMPRISING THE SAME AND THE ELECTRIC VEHICLE COMPRISING THEREOF

The present invention relates to a composite magnetic composite for charging an electric vehicle, comprising magnetic powders having a composite form bonded to each other by a polymer resin, and having excellent physical properties and sufficient impact resistance to be applied to automobiles at the same time, a pad assembly including the same, and a pad assembly comprising the same It relates to electric vehicles, including

An electric vehicle charging system can be basically defined as a system that charges a battery mounted in an electric vehicle using power from a commercial power grid or energy storage device. Such an electric vehicle charging system may have various forms depending on the type of electric vehicle. For example, the electric vehicle charging system may include a conductive charging system using a cable or a non-contact wireless power transmission system. In general, wireless power charging by a wireless power transmission system is a method of charging a battery by flowing a current through electromagnetic induction, and the magnetic field generated by the current flowing in the primary coil of the charger is applied to the secondary coil of the battery. An induced current is generated, which in turn charges the battery with chemical energy. This technology is as safe as the wired charging method because the contacts are not exposed and there is little risk of short circuit.

Recently, as electric vehicles become popular, interest in building charging infrastructure is increasing, and various charging methods such as electric vehicle charging using home chargers, battery replacement, rapid charging devices, and wireless charging devices are already emerging.

As the spread of electric vehicles is expected to increase in the future, a safe and fast charging method that shortens the charging time and increases convenience is required. Various technologies for securing charging efficiency and safety through power charging methods and wireless charging are also trending.

In particular, the impact resistance and charging efficiency of the wireless power charging unit are more important in that the degree of shock that may be caused by an accident in an electric vehicle is large and it is related to the safety of vehicle occupants.

Korean Patent No. 10-1617403 Korean Patent Publication No. 10-2015-0050541

An object of the present invention is to provide a receiver (pad assembly) that generates an induced current by a power supply unit located outside the electric vehicle when charging a battery corresponding to the power of an electric vehicle, and has excellent properties and is suitable for application to automobiles at the same time. An object of the present invention is to provide a composite magnetic composite for charging an electric vehicle having sufficient impact resistance, a pad assembly including the same, and an electric vehicle including the same.

In order to achieve the above object, the magnetic composite for moving means to which electric force is applied according to an embodiment of the present invention includes magnetic powders bonded to each other by a polymer resin, ^{has an area of 60 cm 2} or more, and has an elongation at break of 0.5 to 10%, and is disposed in the power receiver for charging.

The magnetic composite may have an inductance change rate of 0 to 3% before and after an impact applied by free falling from a height of 1 m.

The magnetic composite may have a Q Factor change rate of 0 to 5% before and after an impact applied by free falling from a height of 1 m.

The magnetic composite may have a resistance change rate of 0 to 2.8% before and after an impact applied by free falling from a height of 1 m.

The magnetic composite may be free-falling from a height of 1 m so that the rate of decrease in charging efficiency before and after the applied impact may be 0 to 6.8%.

The charging efficiency may be evaluated at 85 kHz.

The magnetic composite may be in the form of an injection-molded block.

The magnetic composite may be laminated in a sheet form.

The magnetic composite may have a magnetic permeability of 20 to 150,000 in a frequency region of 85 kHz.

In order to achieve the above object, the pad assembly for moving means to which the electric force is applied according to another embodiment of the present invention includes a magnetic composite layer on which the magnetic composite for the moving means for applying the electric force described above is disposed.

In order to achieve the above object, the moving means for applying the electric force according to another embodiment of the present invention includes a magnetic composite for the moving means for applying the electric force described above in the power receiver.

According to the present invention, it is useful to provide a composite magnetic composite having excellent impact resistance suitable for wireless charging of an electric vehicle, a pad assembly including the same, and an electric vehicle including the same.

1 is a configuration diagram showing a wireless power receiver for wireless charging of an electric vehicle according to an embodiment of the present invention.
2 is a perspective view illustrating a wireless power receiver for wireless charging of an electric vehicle according to an embodiment of the present invention.
3 is a perspective view illustrating a state in which a magnetic composite layer is disposed on a pad assembly according to an embodiment of the present invention.
Figure 4 shows the state before (a) and after (b) the impact of the ferrite tested in Comparative Example 1 in the Example of the present invention.
Figure 5 shows the state before (a) and after (b) the impact of the composite magnetic composite tested in Example 1 in the embodiment of the present invention.

Hereinafter, the present invention will be described in more detail through examples. These examples are only for illustrating the present invention in more detail, and it will be apparent to those skilled in the art that the scope of the present invention is not limited by these examples according to the gist of the present invention. .

Throughout this specification, the term "combination of these" included in the expression of the Markush form means one or more mixtures or combinations selected from the group consisting of the components described in the expression of the Markush form, and the components It is meant to include one or more selected from the group consisting of.

Throughout this specification, terms such as “first”, “second” or “A”, “B” are used to distinguish the same terms from each other. Also, the singular expression includes the plural expression unless the context clearly dictates otherwise.

In the present specification, unless otherwise specified, the expression "a" or "a" is interpreted as meaning including the singular or the plural as interpreted in context.

Throughout the specification, when a component is said to be "connected" with another component, it includes not only a case of 'directly connected' but also a case of 'connected with another component interposed therebetween'. In addition, when a component "includes" a component, it means that other components may be further included, rather than excluding other components, unless otherwise stated.

The inventors of the present invention have found that stability is important for a power transmission/reception module applied to a moving means such as an electric vehicle, particularly a reception module, and, unlike a reception module applied to a portable electronic device, shock applied to a vehicle or a vehicle It is possible to receive the noise caused by the vibration of the When the magnetic sheet included in the receiving module is damaged due to such an impact, the power reception efficiency of the receiving module may be significantly reduced, and the present invention has been completed by contemplating supplementary measures for this.

1 is a block diagram illustrating a wireless power receiver for wireless charging of an electric vehicle according to an embodiment of the present invention, and FIG. 2 is a perspective view illustrating a wireless power receiver for wireless charging of an electric vehicle according to an embodiment of the present invention. , FIG. 3 is a perspective view illustrating a state in which a magnetic composite layer is disposed on a pad assembly according to an embodiment of the present invention. Hereinafter, the present invention will be described in more detail with reference to FIGS. 1 to 3 .

In order to achieve the above object, the magnetic composite 310 for an electric vehicle of the present invention includes magnetic powders bonded to each other by a polymer resin. The pad assembly 500 for an electric vehicle according to another embodiment of the present invention includes a magnetic composite layer 300 on which the magnetic composite 310 for an electric vehicle is disposed. The arrangement includes a case in which they are arranged adjacent to each other and a case in which at least a portion of the magnetic composite overlaps each other.

The magnetic composite 310 may be in the form of a sheet having a constant area, or may be in the form of a block having a constant area and thickness.

The magnetic composite layer 300 for an electric vehicle is included in the large area of the charging pad assembly 500 of the electric vehicle, specifically, ^{may be included in an area of 200 cm 2} or more, may be included in an area of 400 cm ² or more, and may be included in an area of 600 cm. ^It may be included in two or more areas. In addition, the magnetic composite layer 300 for an electric vehicle may be included in an area ^{of 10,000 cm 2 or less.} In this way, the magnetic composite layer 300 has a large area, and a method of arranging a plurality of magnetic composites may be applied. At this time, the individual magnetic composite 310 ^{may have an area of 60 cm 2} or more, and an area of 90 cm ² and may have an area of 95 to 900 cm ^{2 .}

As in the present invention, when the magnetic powders are combined with each other by a polymer resin, a magnetic composite with fewer defects and less damage due to impact can be provided over a large area.

The magnetic composite 310 for electric vehicles may have an elongation at break of 0.5% or more. The magnetic composite having such elongation at break is a characteristic that is difficult to obtain in a ceramic magnetic composite that does not apply a polymer, and even if the magnetic composite of a large area is distorted by impact, damage to the sheet itself can be reduced.

Specifically, the elongation at break of the magnetic composite for electric vehicles may be 0.5% or more, 1% or more, and 2.5% or more. There is no particular limitation on the upper limit of the elongation at break, but if the content of the polymer resin is increased to improve the elongation at break, physical properties such as inductance of the magnetic composite may be deteriorated, so the elongation at break is preferably 10% or less.

The magnetic composite 310 for an electric vehicle is characterized in that the change in physical properties before and after impact is small.

Specifically, in the magnetic composite 310 for electric vehicles, the inductance change rate before and after the impact applied by free-falling from a height of 1 m may be less than 5%, and may be less than 3%. It is best that the change rate of the inductance is 0% which does not appear substantially before and after the impact. More specifically, the magnetic composite for electric vehicle may have an inductance change rate of 0 to 3%, 0.001 to 2%, and 0.01 to 1.5% before and after the impact applied by free-falling from a height of 1 m. The magnetic composite for electric vehicles having such an inductance change rate can provide a magnetic composite with improved stability because the inductance change rate before and after impact is relatively small.

The magnetic composite 310 for electric vehicle may have a Q factor change rate of 0 to 5%, 0.001 to 4%, and 0.01 to 2.5% before and after the impact applied by free-falling from a height of 1 m. These values are significantly superior to those of the ferrite magnetic sheet, meaning that the change in physical properties before and after impact is small, so that the stability and impact resistance of the magnetic composite are further improved.

The magnetic composite 310 for electric vehicle may have a resistance change rate of 0 to 2.8%, 0.001 to 1.8%, and 0.1 to 1.0% before and after the impact applied by free falling from a height of 1 m. These values are significantly superior to those of ferrite magnetic composites, and the resistance value change before and after impact is small, so even if the magnetic composite is repeatedly applied in an environment where actual shock and vibration are applied, the resistance value is well maintained below a certain level has

The magnetic composite 310 for electric vehicle may have a rate of decrease in charging efficiency before and after the impact applied by free-falling from a height of 1 m may be 0 to 6.8%, may be 0.001 to 5.8%, and may be 0.01 to 3.4%. This rate of decrease in charging efficiency means that the charging efficiency decreases to a fairly small extent even after impact, which means that a magnetic composite applied over a relatively large area can provide stable physical properties even if impact or distortion occurs repeatedly.

In particular, the charging efficiency is a result of evaluation at less than 100 kHz, for example, 85 kHz, and is a result of evaluation in a band distinct from a frequency applied in a portable electronic device such as a mobile phone.

The magnetic composite 310 for electric vehicles may have a block shape, may have a thickness of 1 mm or more, may have a thickness of 2 mm or more, may have a thickness of 3 mm or more, and may have a thickness of 4 to 6 mm. . Such a block-shaped magnetic composite can be manufactured by injection molding, etc., and has the advantage of being able to manufacture the magnetic composite with a relatively thick thickness.

The magnetic composite 310 for an electric vehicle is in the form of a sheet, and may have a thickness of 80 um or more, and may have a thickness of 85 to 150 um. A conventional film or sheet manufacturing method may be applied to the manufacture of the magnetic composite in the form of a sheet, and there is an advantage in that the magnetic composite can be manufactured in a desired area and size with excellent yield.

When the magnetic composite 310 for electric vehicle is laminated and applied in the form of a sheet, the magnetic composite 310 may be one in which 20 or more sheets of the magnetic composite in the sheet form are laminated, and 50 or more may be laminated. . The magnetic composite 310 for electric vehicle may be stacked in a sheet form in 150 or less sheets, or in 100 or less sheets.

The polymer resin is characterized in that it is cured, and the magnetic composite 310 may contain 85 wt% or more of magnetic powder. Specifically, the magnetic composite may include 85 to 99% by weight of the magnetic powder, and may include 88 to 99% by weight of the magnetic powder.

The magnetic composite 310 for an electric vehicle may have a magnetic permeability of 20 to 150,000 in a frequency region of less than 100 kHz. For example, the magnetic composite 310 for an electric vehicle may have a magnetic permeability of 20 to 150,000 at a frequency of 85 kHz.

Specifically, the magnetic composite for electric vehicle 310 may have a magnetic permeability of 30 to 300 in a frequency region of less than 100 kHz. For example, the magnetic composite 310 for electric vehicles may have a magnetic permeability of 30 to 300 at a frequency of 85 kHz.

Specifically, the magnetic composite 310 for an electric vehicle may have a magnetic permeability of 600 to 3,500 in a frequency region of less than 100 kHz. For example, the magnetic composite 310 for an electric vehicle may have a magnetic permeability of 600 to 3,500 at a frequency of 85 kHz.

Specifically, the magnetic composite 310 for an electric vehicle may have a magnetic permeability of 10,000 to 150,000 in a frequency region of less than 100 kHz. For example, the magnetic composite 310 for an electric vehicle may have a magnetic permeability of 10,000 to 150,000 at a frequency of 85 kHz.

The magnetic composite 310 contains magnetic powder. Magnetic powders include permalloy; sandust; Fe-Si-Al, Fe-Si-Cr, or Fe-Si-B-Cu-Nb-based nanocrystalline; may be a magnetic metal powder comprising a powder or a mixed powder thereof.

The Fe-Si-B-Cu-Nb-based nanocrystals include 70 to 85 mol% of Fe, 10 to 29 mol% of Si and B, and 1 to 5 mol% of Cu and Nb. Examples include Fe73.5CuNb3Si13.5B9 and the like. When such a nanocrystal is included in the magnetic metal powder, better shielding performance can be obtained.

The magnetic powder may have a particle diameter of 3 nm to 1 mm.

The magnetic composite 310 may have heat resistance that can withstand high temperature conditions and corrosion resistance that can withstand various corrosive environments.

As the polymer resin into which the magnetic powder is mixed, a curable resin may be used, and specifically, a photocurable resin, a thermosetting resin, and a high heat-resistant thermoplastic resin may be included. The curable resin may include, but is not limited to, a polyurethane-based resin, an acrylic resin, a polyester resin, an isocyanate resin, or an epoxy resin.

Specifically, the polymer resin may include a polyurethane-based resin, an isocyanate-based curing agent, and an epoxy-based resin.

The polyurethane-based resin may have a number average molecular weight in the range of about 500 to 50,000 g/mol, in the range of about 10,000 to 50,000 g/mol, or in the range of about 10,000 to 40,000 g/mol.

The isocyanate-based curing agent may be an organic diisocyanate.

For example, the isocyanate-based curing agent may be an aromatic diisocyanate, an aliphatic diisocyanate, a substituted aliphatic diisocyanate, or a mixture thereof.

The epoxy-based resin may include a bisphenol-type epoxy resin such as a bisphenol A-type epoxy resin, a bisphenol F-type epoxy resin, a bisphenol S-type epoxy resin, or a tetrabromobisphenol A-type epoxy resin; spiro cyclic epoxy resin; naphthalene type epoxy resin; biphenyl type epoxy resin; terpene type epoxy resin; glycidyl ether type epoxy resins such as tris(glycidyloxyphenyl)methane and tetrakis(glycidyloxyphenyl)ethane; glycidyl amine type epoxy resins such as tetraglycidyl diaminodiphenylmethane; cresol novolac-type epoxy resin; and novolak-type epoxy resins such as phenol novolak-type epoxy resins, α-naprole novolak-type epoxy resins, and brominated phenol novolak-type epoxy resins. These epoxy resins can be used individually by 1 type or in combination of 2 or more type.

The magnetic composite 310 may contain 1 to 15% by weight of the polymer resin, and may include 1 to 12% by weight of the polymer resin.

In addition, the magnetic composite 310 is based on the total weight of the polymer resin, 75 to 85% by weight of a polyurethane-based resin, 10 to 18% by weight of an isocyanate-based curing agent, and 3 to 10% by weight of an epoxy-based resin. (the remaining amount is magnetic powder). When the polymer resin of such a composition is applied as the polymer resin described above, it is possible to provide a magnetic composite with excellent physical properties while making the composite easier to manufacture.

The magnetic composite 310 can be manufactured by a sheet forming process such as mixing magnetic powder and a polymer resin composition to slurry it, then molding it into a sheet shape and curing (thermal curing, etc.), but has a large area having a constant thickness. In order to manufacture the magnetic composite, the composite block may be manufactured by injection molding. In the manufacturing method, a conventional sheeting or blocking method may be applied to the sheeting or blocking method, and the specific method is not particularly limited.

The magnetic composite according to the present invention may further include a heat dissipation sheet (not shown) disposed on the other surface, and a protective layer 400 or an adhesive layer may be additionally laminated on one or the other surface of the magnetic composite and the heat dissipation sheet.

The heat dissipation sheet effectively dissipates heat generated at a hot spot and serves as an intermediate medium serving to transfer to a heat sink or the like, or finally dissipating heat, and a metal foil such as a graphite sheet or copper foil; A carbon nanotube composite sheet or the like can be used.

The protective layer 400 is not particularly limited in material, for example, polyethylene terephthalate (PET), polyethylene (PE), polyvinyl chloride (PVC), polycarbonate (PC), polypropylene (PP) or these It may be a polymer film of a mixed material of

The vehicle pad assembly 500 is located on the receiving pad 100 and is located above or below the receiving coil 200 and the receiving coil connected to the outside through a wire 210, and at least one magnetic complex 310 ) includes a magnetic composite layer 300 arranged side by side or partially overlapping each other, and a cover layer 400 (a protective layer) positioned on the magnetic composite layer. This pad assembly has superior impact resistance and excellent power reception efficiency compared to the existing pad assembly for portable devices (power reception device), and in particular, when applied to automobiles, excellent charging despite the impact that may be caused by internal or external factors Efficiency can be better maintained.

The electric vehicle 1 according to another embodiment of the present invention includes the electric vehicle pad assembly 500 described above. Since the description of the pad assembly for an electric vehicle and the magnetic composite included therein overlaps with the above description, the description thereof will be omitted.

Hereinafter, the present invention will be described in more detail through specific examples. The following examples are merely examples to help the understanding of the present invention, and the scope of the present invention is not limited thereto.

Material of magnetic composite

The materials used in Examples 1 and 2 below were as follows:

- Magnetic Powder: Sandust Powder, C1F-02A, Crystallite Technology

- Polyurethane-based resin: UD1357, Daiichi Seika Industrial Co., Ltd.

- Isocyanate-based curing agent: isophorone diisocyanate, Sigma-Aldrich

- Epoxy resin: Bisphenol A type epoxy resin (epoxy equivalent = 189 g/eq), EpikoteTM 828, Japan Epoxy Resin

- Nylon-based resin: Nylon 12, 3020, Ubesta, Nylon 6, B40, BASF

- PP-based resin: 5030, for emulsification

Example 1: Preparation of sheet-type magnetic composite

Step 1) Preparation of magnetic powder slurry

42.8 parts by weight of magnetic powder, 15.4 parts by weight of polyurethane-based resin dispersion (25% by weight of polyurethane-based resin, 75% by weight of 2-butanone), 1.0 parts by weight of isocyanate-based curing agent dispersion (62% by weight of isocyanate-based curing agent, 25% by weight of n-butyl acetate) weight %, 2-butanone 13% by weight), 0.4 parts by weight of an epoxy resin dispersion (epoxy-based resin 70% by weight, n-butyl acetate 3% by weight, 2-butanone 15% by weight, toluene 12% by weight), and 40.5 parts by weight of toluene was mixed in a planetary mixer at a speed of about 40 to 50 rpm for about 2 hours to prepare a magnetic powder slurry.

Step 2) Preparation of sheet-type magnetic composite

The previously prepared magnetic powder slurry was coated on a carrier film by a comma coater, and dried at a temperature of about 110° C. to form a dry magnetic composite. The dried magnetic composite was compression-hardened by a hot press process at a temperature of about 170° C. and a pressure of about 9 Mpa for about 60 minutes to obtain a sheet-type magnetic composite. The magnetic powder content of the magnetic composite thus prepared was about 90%, and the thickness of one sheet was about 100 um. 40 to 50 sheets of the sheet were laminated to form a magnetic composite having a thickness of 4 to 5 mm, which was then applied to the experiment.

Example 2: Preparation of block-type magnetic composite

A magnetic powder slurry was prepared in the same manner as described in Example 1, except that toluene was not added. Thereafter, a block slurry was obtained at a temperature of 180 to 200° C. through an injection machine without using a carrier film and a comma coater, and a block-type magnetic composite having a width of 10 cm, a length of 10 cm, and a thickness of 4 to 5 mm was prepared. . The magnetic powder content of the magnetic block thus prepared was about 90%. The block-type magnetic composite was prepared in a size of 25 cm and 25 cm by arranging it in a checkerboard shape and applied to the following experiments.

Comparative Example 1: Ferrite magnetic sheet

SKC's Mn-Zn ferrite magnetic sheet was used.

For the purpose of testing the materials applied to the electric vehicle receiver, four or more of the above composite magnetic sheet and ferrite magnetic sheet were prepared in a size of 10 cm wide, 10 cm long, and 4 to 5 mm thick, respectively, and arranged in a checkerboard pattern. and applied to the experiment. Afterwards, the experimental results were expressed as the average of these results.

Evaluation of the properties of magnetic composites

The magnetic composites of Examples 1 and 2 and the sheet of Comparative Example 1 were subjected to an impact in the same manner as described below, and the physical properties before and after applying the impact were evaluated and shown in Table 1 below. .

How to apply shock

The samples of Examples and Comparative Examples were subjected to impact by free-falling from a height of 1 m. Sample photos of Comparative Example 1 and Example 1 before and after applying the above impact are shown in Figure 4 (a: before the impact of Comparative Example 1, b: after the impact of Comparative Example 1) and Figure 5 (a: Example) 1 before impact application, b: after impact application of Example 1).

Evaluation of elongation at break

The elongation at break was measured using a UTM device (INSTRON 5982, INSTRON Corporation), and was measured only for sheet 70um before impact application by the method of ASTM D412 Type C.

Inductance change rate evaluation

The rate of change of inductance was calculated using the LCR Meter (IM3533, HIOKI) by measuring the inductance before and after applying the impact, and the rate of change was calculated in Equation (1) below.

Equation (1) Inductance change rate = 100 * (Inductance before impact application - Inductance after impact application)/(Inductance before impact application)

Evaluation of resistance change rate, Q factor change rate, etc.

The change rate of resistance was calculated by measuring the inductance before and after the impact application using an LCR Meter (IM3533, HIOKI Corporation), and the rate of change was calculated in Equation (2) below.

Equation (2) Resistance change rate = 100 * (resistance before impact application - resistance after impact application)/(resistance before impact application)

In addition, the rate of change of the Q factor was calculated using Equation (3).

Equation (3) Q Factor change rate = 100 * (Q Factor value before shock application- Q Factor value after shock application)/(Q Factor before shock application)

where, Q Factor = (inductance x frequency x 2π/resistance)

Evaluation of the degree of decrease in charging efficiency

The charging efficiency was evaluated under the same conditions with an output power of 1 kw at 85 kHz frequency, respectively, in the case of applying the sheet before impact application and the case of applying the sheet after impact application.

The degree of decrease in charging efficiency was evaluated by calculating in Equation (4) below, and the values are shown in Table 1 below.

Equation (4) Reduction of charging efficiency = 100 * (Charging efficiency before application of shock- Charging efficiency after application of shock)/(Charging efficiency before application of shock)

For all measurements, the coil and frame of the SAE J2954 WPT1 Z2 Class standard TEST standard are applied, and the receiving pad (35.5cmX35.5cm) and the transmitting pad (67.48cmX59.1cm) are manufactured by stacking magnetic materials, spacers, and aluminum plates, and measuring 85 kHz. did.

is it a shock Elongation at break inductance Q Factor resistance charging efficiency
Comparative Example 1 I'm 0 230 481 263 94 after 0 218 414 290 91
Example 1 I'm 3% 225 444 279 93 after 3% 225 442 280 93
Example 2 I'm 3% 225 444 279 93 after 3% 224 441 280 92.8

(%) Elongation at break
inductance change
Q Factor rate of change resistance change rate
Reduced charging efficiency
Comparative Example 1 0 5.2 14 10.3 3 Example 1 3 0 0.36 0.36 0 Example 2 3 0.4 0.8 0.36 0.02

Referring to the results of Table 1 above, the rate of change of factors such as inductance, Q Factor, and resistance before and after impact compared to the sheet of Comparative Example 1 in which the sheet of Example 1 having an average elongation at break of 3% is a ferrite sheet In the range of 0 to 1, it was confirmed that only a very slight change appeared before and after the impact application. On the other hand, the sheet of Comparative Example 1 showed a significant level of change in factors such as inductance, Q factor, and resistance. decrease could be observed. From this, it was confirmed that the sheet of Example 1 was more excellent to be applied stably as a receiving pad of a wireless charger in an environment where an impact is easy to be applied in the driving process, such as an electric vehicle. Although the preferred embodiment of the present invention has been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art using the basic concept of the present invention as defined in the following claims are also provided. is within the scope of the

1: Electric vehicle 2: Power supply
10: receiving device, power receiving device 100: receiving pad
200: receiving coil 210: wire
300: magnetic composite layer 310: magnetic composite
400: cover layer, protective layer 500: pad assembly for electric vehicles

Claims (10)

It contains magnetic powders bonded to each other by a polymer resin, ^{has an area of 95 to 900 cm 2} , has an elongation at break of 0.5 to 10%, and is disposed in a charging power receiver,
A magnetic composite for moving means applying electric force, in which the rate of change of inductance before and after the impact applied by free fall from a height of 1 m is 0 to 3%.
It contains magnetic powders bonded to each other by a polymer resin, ^{has an area of 95 to 900 cm 2} , has an elongation at break of 0.5 to 10%, and is disposed in a charging power receiver,
A magnetic composite for moving means applying electric force, in which the rate of change of the Q factor before and after the impact applied by free fall from a height of 1 m is 0 to 5%.
It contains magnetic powders bonded to each other by a polymer resin, ^{has an area of 95 to 900 cm 2} , has an elongation at break of 0.5 to 10%, and is disposed in a charging power receiver,
A magnetic composite for moving means applying electric force, in which the rate of change of resistance before and after the impact applied by free fall from a height of 1 m is 0 to 2.8%.
It contains magnetic powders bonded to each other by a polymer resin, ^{has an area of 95 to 900 cm 2} , has an elongation at break of 0.5 to 10%, and is disposed in a charging power receiver,
A magnetic composite for moving means applying electric force, in which the rate of decrease in charging efficiency before and after the impact applied by free fall from a height of 1 m is 0 to 6.8%.
5. The method of claim 4,
The charging efficiency is evaluated at 85 kHz, a magnetic composite for moving means applying electric force.
According to claim 1,
In the form of injection-molded blocks, magnetic composites for moving means that apply electric force.
According to claim 1,
A magnetic composite for a means of moving that applies electric force, in which the sheet form is laminated.
According to claim 1,
A magnetic composite for moving means applying electric force, having a magnetic permeability of 20 to 150,000 in a frequency range of 85 kHz.
A pad assembly for moving means applying an electric force, comprising a magnetic composite layer on which a magnetic composite for moving means for applying an electric force according to any one of claims 1 to 4 is disposed.
A moving means for applying an electric force, comprising a pad assembly for a moving means for applying the electric force according to claim 9.

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