CN221552881U

CN221552881U - Battery charger

Info

Publication number: CN221552881U
Application number: CN202420043097.3U
Authority: CN
Inventors: 陈进添; 吴良贵; 王茂林; 李如飞
Original assignee: Fujian Nanping Nanfu Battery Co Ltd
Current assignee: Fujian Nanping Nanfu Battery Co Ltd
Priority date: 2024-01-08
Filing date: 2024-01-08
Publication date: 2024-08-16
Anticipated expiration: 2034-01-08

Abstract

The utility model discloses a battery charger. The battery charger may include a battery compartment and a positive pole portion. The battery compartment is provided with a battery compartment extending in a first direction. The battery compartment is for selectively receiving one of an AA-type battery and an AAA-type battery. The positive electrode portion is located at an end of the battery can in the first direction. The positive electrode portion includes a first positive electrode protrusion and a second positive electrode protrusion formed to extend in a first direction toward the battery case. The first positive electrode protrusion and the second positive electrode protrusion are disposed at intervals in the third direction. And the second positive electrode protrusion is closer to the bottom of the battery compartment than the first positive electrode protrusion in the third direction. The first positive electrode tab is adapted to contact the positive electrode of an AA-sized battery located in the battery compartment. The first positive electrode protrusion and the second positive electrode protrusion commonly contact the positive electrode of the AAA battery located in the battery case. The utility model can share the positive pole part when the AA type battery and the AAA type battery are respectively placed in the battery groove, thereby being beneficial to simplifying the structure of the battery charger.

Description

Battery charger

Technical Field

The present utility model relates generally to the field of battery charging, and more particularly to a battery charger.

Background

The battery charger in the related art is generally separately provided for contacting the positive electrode portion of the positive electrode of the battery when matching batteries of different models. Therefore, the structure of the battery charger is complex, the production is inconvenient, and the miniaturization of the charger is also inconvenient.

Accordingly, there is a need to provide a battery charger that at least partially addresses the above-described problems.

Disclosure of utility model

In the summary, a series of concepts in a simplified form are introduced, which will be further described in detail in the detailed description. The summary of the utility model is not intended to define the key features and essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

To at least partially solve the above problems, the present utility model provides a battery charger including:

The battery compartment is provided with a battery groove extending along a first direction, and the battery groove is used for selectively accommodating one of an AA type battery and an AAA type battery; and

The positive electrode part is positioned at the end part of the battery groove along the first direction, the positive electrode part comprises a first positive electrode bulge and a second positive electrode bulge which are formed by extending towards the battery groove in the first direction, the first positive electrode bulge and the second positive electrode bulge are arranged at intervals in a third direction, the second positive electrode bulge is closer to the bottom of the battery compartment than the first positive electrode bulge in the third direction, the third direction is parallel to the direction of a notch of the battery groove and is perpendicular to the first direction,

The positive electrode portion is configured such that:

The first positive electrode bulge contacts with the positive electrode of the AA type battery in the battery groove, and the first positive electrode bulge and the second positive electrode bulge jointly contact with the positive electrode of the AAA type battery in the battery groove.

According to the battery charger of the utility model, the battery tank is arranged in the battery compartment to selectively accommodate the AA type battery or the AAA type battery, and the positive electrode part is arranged at the end part of the battery tank to be connected with the positive electrode of the battery. When the AA type battery is positioned in the battery groove, the positive electrode of the AA type battery is abutted with the first positive electrode bulge of the positive electrode part; when the AAA type battery is positioned in the battery groove, the positive electrode of the AAA type battery is abutted against the first positive electrode bulge and the second positive electrode bulge. Therefore, when the AA type battery and the AAA type battery are respectively placed in the battery groove, the positive electrode part can be shared, so that the structure of the battery charger is simplified, the production and the manufacturing are convenient, and the miniaturization of the battery charger is facilitated.

Optionally, the first positive electrode protrusion is closer to a center of the battery can in the first direction than the second positive electrode protrusion is in the first direction.

Optionally, the battery compartment includes a positive end wall corresponding to an end of the battery slot, the positive end wall is provided with a positive groove, a notch of the positive groove faces the battery slot along the first direction, and a dimension of the positive groove along the second direction is greater than a radial outer dimension of a positive pole of the AA battery and less than a radial outer dimension of the AAA battery;

The positive electrode portion is located inside the positive electrode groove, and the positive electrode portion does not exceed a surface of the positive electrode end wall facing the battery case in the first direction.

Optionally, the battery compartment has a top and a bottom opposite in a third direction, the battery compartment being located at the top of the battery compartment, the third direction being perpendicular to the first direction and the second direction;

The size of the positive electrode groove along the second direction is increased in a direction parallel to the third direction and facing away from the battery groove.

Optionally, the positive electrode groove penetrates a bottom of the battery compartment in the third direction to allow the positive electrode portion to move in and out of the positive electrode groove.

Optionally, the battery charger further comprises a bottom cover connected to the bottom of the battery compartment, and a containing cavity is formed between the bottom cover and the battery compartment;

the battery charger further includes a circuit board located in the receiving cavity, and the positive electrode portion is connected to the circuit board.

Optionally, the battery charger further comprises an interface member connected to the circuit board, the interface member configured to connect to an external power source.

Optionally, the battery charger further comprises a charge indicator light connected to the circuit board;

The battery charger further comprises a cover that is openably connected to the top of the battery compartment, wherein

The surface cover is constructed to be light-permeable; or alternatively

The surface cover comprises a first window part capable of transmitting light, and the first window part is arranged corresponding to the charging indicator lamp.

Optionally, the battery case includes a first case portion for accommodating an AA-type battery and a second case portion for accommodating an AAA-type battery, the second case portion being located inside the first case portion,

The battery charger comprises a battery compartment, a first groove part, a second groove part, a first negative electrode part, a second negative electrode part, a battery compartment and a battery cover, wherein the first groove part and the second groove part share the same positive electrode part, the battery charger further comprises a first negative electrode part and a second negative electrode part, the first negative electrode part is correspondingly arranged at the end part of the first groove part, which is far away from the positive electrode part, the second negative electrode part is correspondingly arranged at the end part of the second groove part, which is far away from the positive electrode part, and the second negative electrode part is far away from the top of the battery compartment in a third direction than the first negative electrode part.

Optionally, a pick-and-place groove is formed in the top of the battery compartment, the direction of the notch of the pick-and-place groove is the same as the direction of the notch of the battery compartment, the pick-and-place groove is located at the end of the battery compartment along the second direction and is communicated to the battery compartment along the second direction, and the second direction is perpendicular to the first direction.

Drawings

The following drawings of embodiments of the present utility model are included as part of the utility model. Embodiments of the present utility model and their description are shown in the drawings to explain the principles of the utility model. In the drawings of which there are shown,

FIG. 1 is an exploded view of a battery charger according to an embodiment of the present utility model, in which a AAA type battery and an AA type battery are respectively installed in a battery compartment;

FIG. 2 is a schematic top view of a battery compartment of the battery charger shown in FIG. 1, wherein a AAA type battery and an AA type battery are respectively mounted within the battery compartment;

FIG. 3 is a cross-sectional view taken along line A-A of FIG. 2;

FIG. 4 is a schematic view of the battery compartment shown in FIG. 2 without a battery mounted thereto;

FIG. 5 is a cross-sectional view taken along line B-B of FIG. 4;

FIG. 6 is a schematic view of the battery compartment shown in FIG. 2 with one AAA type battery and one AA type battery mounted in other battery compartments;

FIG. 7 is a cross-sectional view taken along line C-C of FIG. 4;

FIG. 8 is an enlarged schematic view of the portion I in FIG. 7;

fig. 9 is a schematic view showing the structure of a rechargeable battery according to an embodiment of the present utility model;

FIG. 10 is an enlarged schematic view of the battery charger shown in FIG. 1 in the position of the positive end wall;

Fig. 11 is an enlarged schematic view of the battery charger shown in fig. 1 at a positive pole position;

FIG. 12 is an enlarged schematic view of the battery charger shown in FIG. 1 in a negative pole position;

FIG. 13 is a schematic cross-sectional view of the battery charger shown in FIG. 1 in a negative portion position; and

Fig. 14 is a perspective view of a battery compartment in the battery charger shown in fig. 1.

Reference numerals illustrate:

1: AA battery 1a: positive pole

1B: negative electrode sheet 1c: insulating ring

2: AAA battery 101: battery compartment

101A: first groove 101b: a second groove part

101C: positive electrode end wall 101d: positive electrode groove

101K: a second window portion 101m: pick-and-place groove

102: Face cover 102a: a first window part

103: Bottom cover 104: light guide

105: The housing chamber 110: electrical component

112: Positive electrode portion 112a: first positive electrode protrusion

112B: second positive electrode protrusion 113: a first negative electrode part

115: Second negative electrode portion 120: interface component

150: Charging indicator light 170: circuit board

D1: first direction D2: second direction

D3: third direction of

Detailed Description

In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present utility model. It will be apparent, however, to one skilled in the art that embodiments of the utility model may be practiced without one or more of these details. In other instances, well-known features have not been described in detail in order to avoid obscuring the embodiments of the utility model.

In the following description, a detailed structure will be presented for a thorough understanding of embodiments of the present utility model. It will be apparent that embodiments of the utility model may be practiced without limitation to the specific details that are set forth by those skilled in the art.

It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the utility model, as the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises," "comprising," and/or "including," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

Ordinal numbers such as "first" and "second" cited in the present utility model are merely identifiers and do not have any other meaning, such as a particular order or the like. Also, for example, the term "first component" does not itself connote the presence of "second component" and the term "second component" does not itself connote the presence of "first component". It is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "inner", "outer" and the like are used herein for illustrative purposes only and are not limiting.

Hereinafter, specific embodiments of the present utility model will be described in more detail with reference to the accompanying drawings, which illustrate representative embodiments of the present utility model and not limit the present utility model.

Referring to fig. 1-14, the present utility model provides a battery charger. The battery charger may include a battery compartment and an electrical assembly 110. The battery compartment is provided with a battery compartment extending in a first direction D1. The battery compartment is for selectively accommodating one of the AA-type battery 1 and the AAA-type battery 2. That is, the battery case may accommodate any one of the AA type battery 1 and the AAA type battery 2 at different times. The electrical component 110 includes a positive portion 112 for contact with the positive terminal of the battery. The positive electrode 112 is located at an end of the battery can in the first direction D1. The positive electrode portion 112 includes a first positive electrode protrusion 112a and a second positive electrode protrusion 112b formed to extend in the first direction D1 facing the battery can. The first positive electrode tab 112a and the second positive electrode tab 112b are disposed at intervals in the third direction D3. And the second positive electrode protrusion 112b is closer to the bottom of the battery compartment 101 than the first positive electrode protrusion 112a in the third direction D3. The third direction D3 is parallel to the orientation of the slots of the battery compartment and perpendicular to the first direction D1. The first direction D1 may be understood as a slot length direction of the battery slot, the slot width direction of the battery slot may be referred to as a second direction D2, and the third direction D3 may be understood as a slot depth direction of the battery slot or a height direction of the battery compartment 101.

The positive electrode portion 112 is configured such that: the first positive electrode protrusion 112a contacts the positive electrode of the AA type battery 1 positioned in the battery can. The first positive electrode protrusion 112a and the second positive electrode protrusion 112b commonly contact the positive electrode of the AAA battery 2 located in the battery can.

According to the battery charger of the present utility model, the battery compartment is provided with the battery groove for selectively accommodating the AA type battery 1 or the AAA type battery 2, and the positive electrode portion 112 is provided at the end of the battery groove for connecting the positive electrode of the battery. When the AA type battery 1 is positioned in the battery groove, the positive electrode of the AA type battery 1 is abutted against the first positive electrode bulge 112a of the positive electrode part 112; when the AAA type battery 2 is positioned in the battery can, the positive electrode of the AAA type battery 2 abuts against the first positive electrode protrusion 112a and the second positive electrode protrusion 112b. Thus, when the AA type battery 1 and the AAA type battery 2 are placed in the battery case, the positive electrode 112 can be shared, which contributes to simplification of the structure of the battery charger, convenience in production and manufacture, and downsizing of the battery charger.

For example, the positive electrode portion 112 may be configured as an elastically deformable conductive metal sheet. When the first and second positive electrode protrusions 112a and 112b of the positive electrode portion 112 are abutted against the battery, elastic force can be applied to the battery by utilizing elastic deformation of the conductive metal sheet, so that the conductive metal sheet can be reliably brought into conductive contact with the battery.

Referring to fig. 3, 5 and 11, further, the first positive electrode protrusion 112a is closer to the center of the battery can in the first direction D1 than the second positive electrode protrusion 112b is to the center of the battery can in the first direction D1. Therefore, the first positive electrode bulge 112a can apply a certain acting force to the positive electrode terminal of the AA type battery 1 when the AA type battery 1 is installed, so that falling is avoided, and meanwhile, the first positive electrode bulge 112a and the second positive electrode bulge 112b are matched to play a limiting role to the positive electrode terminal of the AAA type battery 2 when the AAA type battery 2 is installed, so that the AAA type battery 2 is better fixed.

Optionally, the battery compartment includes a positive end wall 101c corresponding to an end of the battery can, the positive end wall 101c being provided with a positive recess 101d. The notch of the positive electrode groove 101D faces the battery can in the first direction D1. The size of the positive electrode groove 101D in the second direction D2 is larger than the radially outer size of the positive electrode post of the AA-size battery 1 and smaller than the radially outer size of the AAA-size battery 2. For example, the size of the positive electrode groove 101D in the second direction D2 is greater than 5mm and less than 10mm. The first direction D1 is perpendicular to the second direction D2. As shown in fig. 6, 7 and 8, the positive electrode portion 112 is located inside the positive electrode groove 101d. And the positive electrode portion 112 does not protrude beyond the surface of the positive electrode end wall 101c facing the battery can in the first direction D1, so that the negative electrode of the battery cannot contact the positive electrode portion 112 when the battery is reversely connected. Normally, the diameter of the positive electrode post of the AA type battery 1 is at most 5.5mm, and the maximum value of the outer diameter of the aaa type battery 2 is 9.5mm. By defining the dimensions of the positive electrode groove 101D in the second direction D2, the positive electrode posts of the AA type battery 1 and the AAA type battery 2 are allowed to enter the positive electrode groove 101D to be connected with the positive electrode portion 112, while the negative electrodes of the AAA type battery 2 and the AA type battery 1 can be prevented from entering the positive electrode groove 101D, thereby achieving the purpose of preventing reverse connection of the batteries.

The positive electrode groove 101d formed in the positive electrode end wall 101c can be used for accommodating a positive electrode terminal of a battery, and can play a role in blocking a negative electrode of the battery when the battery is reversely connected, so that the influence of the reverse connection of the battery on the use safety of the battery is avoided. The size range of the positive electrode groove 101D along the second direction D2 is determined according to the heights of the positive electrode terminals of the AA type battery 1 and the AAA type battery 2, so that the AA type battery 1 and the AAA type battery 2 can be simultaneously matched, and the positive electrode part 112 arranged in the positive electrode groove 101D can be used for being in butt joint with the positive electrode terminals of the batteries to realize charging.

As shown in fig. 1 and 10, the battery compartment 101 has a top and a bottom opposite to each other along the third direction D3, the battery groove is located at the top of the battery compartment 101, and the size of the positive electrode groove 101D along the second direction D2 increases in a direction parallel to the third direction D3 and away from the notch of the battery groove, so as to prevent the battery from being separated from the battery groove along the third direction D3 during charging, and affect the charging effect. The positive electrode groove 101D penetrates the bottom of the battery compartment 101 in the third direction D3 to allow the positive electrode portion 112 to move in and out of the positive electrode groove 101D, thereby facilitating the installation and maintenance of the positive electrode portion 112 and also facilitating the installation of the battery.

For example, the positive electrode groove 101D penetrates the bottom of the battery compartment 101 in the third direction D3 to allow the positive electrode portion 112 to move in and out of the positive electrode groove 101D. This facilitates the loading of the positive electrode 112 from the bottom of the battery compartment 101 and the removal of the positive electrode 112.

As shown in fig. 1, the battery charger includes a bottom cover 103, the bottom cover 103 being connected to the bottom of the battery compartment 101, a receiving chamber 105 being formed between the bottom cover 103 and the battery compartment 101; the electrical component 110 further includes a circuit board 170, the circuit board 170 is located in the accommodating cavity 105, the positive electrode portion 112, the first negative electrode portion 113 and the second negative electrode portion 115 are all connected to the circuit board 170, and in specific assembly, the electrical component 110 is first mounted to the battery compartment 101 from the bottom of the battery compartment 101, and then the bottom cover 103 is mounted, so that accommodating and supporting are formed for the electrical component 110.

The electrical assembly 110 may further include an interface member 120, the interface member 120 being generally disposed at one side of the electrical assembly 110, a notch for allowing the interface member 120 to pass through may be disposed between the battery compartment 101 and the bottom cover 103, so that the interface member 120 may be connected to a corresponding connector, the interface member 120 may be, for example, a USB interface or a Type-C interface, the interface member 120 may be connected to the circuit board 170, and the interface member 120 may be used to connect to an external power source, and to supply power to the circuit board 170 inside the battery compartment 101, thereby charging the battery.

In addition, the electrical component 110 may also include a charge indicator light 150. The charge indicator light 150 is connected to the circuit board 170. The circuit board 170 is used to provide power and control for the charge indicator light 150. The charge indicator light 150 can indicate the state of charge, and is convenient for the user to use. The battery charger may further include a cover 102, where the cover 102 is openably connected to the top of the battery compartment 101, and the cover 102 is easy to mount or dismount the battery when opened, and can protect the battery when closed (e.g., to prevent dust, water, knocks, battery detachment, etc.).

In one example, the cover 102 may be configured to be light transmissive, such as a transparent plastic panel, to facilitate a user's viewing of the status of the charge indicator light 150.

In one example, as shown in fig. 1, a first window portion 102a capable of transmitting light is provided in the cover 102. The first window 102a is provided corresponding to the charge indicator lamp 150. As shown in fig. 2 and 14, a second window portion 101k that can transmit light is provided in the battery compartment 101 in a position corresponding to the charge indicator lamp 150, and cooperates with the first window portion 102a to facilitate the user's observation of the charge indicator lamp 150.

As shown in fig. 2, each battery case includes a first case portion 101a for accommodating the AA type battery 1 and a second case portion 101b for accommodating the AAA type battery 2, wherein the second case portion 101b is located inside the first case portion 101a, and the first case portion 101a and the second case portion 101b may share the same positive electrode portion 112. As shown in fig. 3, the extending direction of the first groove portion 101a is parallel to the first direction D1, and a certain angle exists between the extending direction of the second groove portion 101b and the first direction D1, which is beneficial to making the structure of the whole battery charger more compact. The electrical component 110 further includes a first negative electrode portion 113 and a second negative electrode portion 115, where the first negative electrode portion 113 is correspondingly disposed at an end of the first groove portion 101a far from the positive electrode portion 112, and the second negative electrode portion 115 is correspondingly disposed at an end of the second groove portion 101b far from the positive electrode portion 112, and the first negative electrode portion 113 and the second negative electrode portion 115 may be configured as, for example, metal elements having a certain elasticity, and cooperate with the positive electrode portion 112 to apply a force to both ends of the battery so as to fix the battery.

As shown in fig. 12 and 13, the second negative electrode portion 115 is further away from the top of the battery compartment 101 in the third direction D3 than the first negative electrode portion 113, wherein the third direction D3 is parallel to the orientation of the notch of the battery slot and perpendicular to the first direction D1 and the second direction D2, the first negative electrode portion 113 is for interfacing with the negative electrode of the AA-size battery 1, and the second negative electrode portion 115 is for interfacing with the negative electrode of the AAA-type battery 2, enhancing the practicality and suitability of the battery charger.

As shown in fig. 9, the rechargeable battery includes a battery cathode, an insulating ring 1c and a battery anode, the insulating ring 1c is connected between the battery anode and the battery cathode to disconnect the battery anode from the battery cathode, the battery anode is located in the ring of the insulating ring 1c, and the insulating ring 1c protrudes from the outer surface of the battery anode in the length direction of the rechargeable battery. The insulating ring 1c is used for contacting the positive end wall 101c when the battery negative electrode faces the positive end wall 101c so as to prevent the battery negative electrode from contacting the positive electrode part 112, the battery positive electrode comprises a positive electrode post 1a used for contacting the positive electrode part 112, the battery negative electrode comprises a negative electrode plate 1b used for contacting the first negative electrode part 113 and the second negative electrode part 115, and the insulating ring 1c arranged on the battery contacts the positive end wall 101c when the battery is reversely connected so as to avoid damage to the battery caused by electrifying. The rechargeable battery and the battery charger provided by the utility model can prevent the battery from being damaged after the battery is reversely installed and electrified, and the battery charger and the rechargeable battery together form a more stable and safer battery charging system.

In the example of fig. 1-8, the battery charger also includes a light guide 104. The light guide 104 is provided corresponding to the first negative electrode portion 113 and the second negative electrode portion 115. For some batteries with the negative electrode capable of emitting light in the charging state, the light guide 104 can penetrate through the light emitted by the negative electrode of the battery, so that the light emitting area is enlarged, the user can observe the charging state of the battery conveniently, and whether the battery is reversely connected can be judged according to the light emitting area.

Referring to fig. 14, the battery compartment 101 is provided at the top of both ends thereof in the second direction D2 with a pick-and-place groove 101m. The pick-and-place groove 101m is located at an end of the battery compartment 101 in the second direction D2 and communicates to the battery groove in the second direction D2. In a plane perpendicular to the second direction D2, the projection of the pick-and-place groove 101m overlaps the first groove portion 101a and the second groove portion 101b. The orientation of the notch of the pick-and-place groove 101m is the same as the orientation of the notch of the first groove portion 101 a. The provision of the pick-and-place groove 101m can facilitate the user to take out the battery located in the first groove portion 101a or the second groove portion 101b.

Unless defined otherwise, technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this utility model pertains. The terminology used herein is for the purpose of describing particular implementations only and is not intended to be limiting of the utility model. Terms such as "disposed" or the like as used herein may refer to either one element being directly attached to another element or one element being attached to another element through an intermediate member. Features described herein in one embodiment may be applied to another embodiment alone or in combination with other features unless the features are not applicable or otherwise indicated in the other embodiment.

The present utility model has been described in terms of the above embodiments, but it should be understood that the above embodiments are for purposes of illustration and description only and are not intended to limit the utility model to the embodiments described. Those skilled in the art will appreciate that many variations and modifications are possible in light of the teachings of the utility model, which variations and modifications are within the scope of the utility model as claimed.

Claims

1. A battery charger, the battery charger comprising:

The positive electrode portion is configured such that:

2. A battery charger as defined in claim 1, wherein,

The first positive electrode protrusion is closer to a center of the battery container in the first direction than the second positive electrode protrusion is in the first direction.

3. A battery charger as claimed in claim 1 or 2, wherein,

The battery compartment comprises an anode end wall corresponding to the end part of the battery groove, the anode end wall is provided with an anode groove, the notch of the anode groove faces the battery groove along the first direction, and the size of the anode groove along the second direction is larger than the radial outer size of an anode post of the AA type battery and smaller than the radial outer size of the AAA type battery;

4. A battery charger as defined in claim 3, wherein,

The battery compartment has a top and a bottom opposite in a third direction, the battery compartment being located at the top of the battery compartment, the third direction being perpendicular to the first direction and the second direction;

5. A battery charger as defined in claim 4, wherein,

The positive electrode groove penetrates a bottom of the battery compartment in the third direction to allow the positive electrode portion to move in and out of the positive electrode groove.

6. A battery charger as claimed in claim 1 or 2, wherein,

The battery charger further comprises a bottom cover, wherein the bottom cover is connected to the bottom of the battery compartment, and a containing cavity is formed between the bottom cover and the battery compartment;

7. The battery charger of claim 6 wherein the battery charger is configured to receive the battery charger,

The battery charger also includes an interface member connected to the circuit board, the interface member configured to connect to an external power source.

8. The battery charger of claim 6 wherein the battery charger is configured to receive the battery charger,

The battery charger further comprises a charging indicator light connected to the circuit board;

The surface cover is constructed to be light-permeable; or alternatively

9. A battery charger as defined in claim 4, wherein,

The battery groove comprises a first groove part used for accommodating an AA type battery and a second groove part used for accommodating an AAA type battery, the second groove part is positioned inside the first groove part,

10. The battery charger of claim 4 wherein the top of the battery compartment is provided with a pick-and-place slot, the orientation of the slot opening of the pick-and-place slot is the same as the orientation of the slot opening of the battery compartment, the pick-and-place slot is located at the end of the battery compartment along a second direction and is communicated to the battery compartment along the second direction, and the second direction is perpendicular to the first direction.