BATTERY CARD AND ELECTRICAL APPARATUS USING SAME BATTERY CARD ASSEMBLY

Abstract: A battery power supply system consisting of battery card, battery card assembly where battery card slots in, and charger where battery card gets recharged is disclosed. The standardized battery card is designed in light, thin, safe, and user-friendly card configuration to make interchangeability between appliances easy and possible. In addition, outside the battery card there is an injection mechanism that fits the battery card in the battery card assembly when slot-in and inject-out, and inside the battery card there is a built-in fuel gauge circuit that regulates voltage with an LED indicator. The battery card assembly is designed either for single or multiple battery cards. In the case of using single battery card, the battery card assembly connects to a power buffer in the electrical apparatus so the user can change their battery card without turning off the electrical apparatus within a certain time interval. In the case of multiple battery cards, the battery card assembly connects power to the electrical apparatus from only one of the battery cards. Until the first battery card is completely discharged, the battery card assembly automatically switches to another battery card without disturbing the electrical apparatus operation.

Description: BATTERY CARD AND ELECTRICAL APPARATUS USING SAME BATTERY CARD ASSEMBLY FIELD OF THE INVENTION The present invention relates to a battery pack and an electrical apparatus using the battery pack, and more particularly to a battery card and an electrical apparatus using same battery card assembly. BACKGROUND OF THE INVENTION At the present time, all portable electrical apparatus including portable information appliances use internal battery pack for energy source. Battery pack contains several battery cells in series and/or in parallel arrangement, making the desired capacity and voltage to operate the appliance. Battery cells in battery pack for portable infoπnation appliances are of two major categories, i.e., nickel metal hydride (NiMH) and lithium ion (Li-ion), because of their relatively high energy density. Conventional battery cells are configured in cylindrical and/or prismatic structures. Fig. 1 shows a cross-section view of a conventional battery cell in a cylindrical structure. As shown in Fig. 1 , attaching media 1 1 with anode layer 12 and attaching media 13 with cathode layer 14 dissociated by a separator 15 are winded in a cylindrical can 16. making the most popular battery cell in cylindrical stnictiire. Fig 2 shows a cross-section view of a conventional battery cell in prismatic stnictiire. As shown in Fig. 2. attaching media 21 with anode layer 22 and attaching media 23 with cathode layer 24 dissociated by a separator 25 are winded in a prismatic can 26, making rectangular battery cell for special applications. Generally speaking, battery pack stnictures are determined by battery cell configurations. Conventional battery packs are bulky, heavy, and expensive when multiple battery cells are integrated. Fig. 3 shows an industry standard battery pack for notebook computers. The battery pack 3 contains several cylindrical Li-ion battery cells 31 , with a circuitry board 32 embedded to gauge fuel and to monitor voltage/current when charging and discharging. In addition, the battery pack 3 has a five-pin output jack 33 connected to the notebook computer. Two of them are terminals for power transmission, the "+" and the "- " '. Others are reserved for communication between battery pack 3 and computer (not shown) for battery cell temperature, battery cell data code, and voltage/current status of the battery pack. In Fig. 3 there are nine cylindrical battery cells 3 1 arranged in the battery pack 3, three in series and three in parallel. Each battery cell 3 1 sizes 18mm in diameter, 65mm in height, operating at 3.6V with a full capacity of 1.35 All. The battery pack 3 consisting of nine cylindrical battery cells 31 delivers 44Wh ( 10.8V x 4.05A ) with 150(W) x 90(L) x 21(T) mm. in size and 490 grams in weight. Such a battery pack 3 is able to operate a Pentium 300 notebook computer for approximately 3 hours ( 180 minutes). Lately battery packs are designed as thin and light as possible in an attempt to fit slimmer and more compact appliances. Fig. 4 shows a slim battery pack for notebook computers containing prismatic battery cells. As shown in Fig 4, the batteiy pack 4 contains several prismatic Li-ion battery cells 41 , with a circuitry board 42 embedded to gauge fuel and to monitor voltage/current when charging and discharging. In addition, the battery pack 4 has a five-pin output jack 43 connected to notebook computer. Two of them are terminals for power transmission, the *i ÷ *' and the "-". Others are reserved for communication between battery pack 4 and computer (not shown) for battery cell temperature, battery cell data code, and voltage/current status of the battery pack. Compared to the battery pack 3 of Fig. 3, the battery pack 4 of Fig. 4 has a reduced dimension in thickness because of using prismatic battery cells 41 , normally less than 10mm. However, battery nin time is compromised because less conducting materials are used in smaller battery cells. Users have found difficulty in maintaining power continuity. With more frequent power shortage, data integrity becomes vulnerable in some worst scenarios. In general, notebook computers incorporate only one battery pack. For heavy users, however, there are notebook computers mounted with two battery packs. They are not considered practical as weight and inconvenience are in concern. In addition, all battery packs are not interchangeable with each other because of the design limitation so that customers cannot replace the battery pack unless from original device maker. Users are confined by inflexible battery pack form factor. Appliance manufacturers, as a result, are able to control battery accessory market at hefty prices with limited availability. Specifically designed battery packs usually present specific safety concerns when inadvertently used outside the manufacturer's recommended guidelines. Recently, in-seat power supply system on aircraft has drawn public attention because users rarely detect battery health before they charge their battery in flight. Manufacturers have recommended Federal Aviation Administration (FAA) to place a moratorium on the use until safety issues can be resolved. All listed disadvantages are obstacles to popularize portable information appliances. The present invention provides solutions with an entirely shifted paradigm. SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide standardized battery packs in light, thin, safe, and user-friendly card configuration to make interchangeability between appliances easy and possible. It is still an object of the present invention to provide a battery power system that provides non-inteπτιptible energy by easy swapping battery packs in user-friendly formats so that the user can change their battery packs without turning off the electrical apparatus when the battery pack nms short of capacity. Therefore, the improved battery power system enables a user to solve the shorter nm time dilemma, as portability requires battery packs continue to shrink. Instead of adding more power to appliance, the present invention brings a different pattern using battery cards to provide a minimum nm time that satisfies general applications whereas the system upholds power continuity. It is further an object of the present invention to provide a safe batteiy power system, by which issues of public safety can be minimized without adding any inconvenience to mobile users when battery cards are charged on a separate charger outside the appliance or a charger built-in the appliance. It is further an object of the present invention to provide an improved battery power system, which enables the user to carry no more power than they actually need and no longer worry losing data when battery power exhausts. It is yet an object of the present invention to provide a battery pack having a safety design to prevent from shortage due to mishandling when the battery pack is not in use. It is still more an object of the present invention to provide a battery- pack having higher weight and volume energy density than that of conventional battery packs. The present invention provides a battery card which is adapted to be used with an electrical apparatus to be power-supplied by the battery card. The battery card of the present invention contains several power- supplying cells (at least one power-supplying cell) in series and/or in parallel arrangement, making the desired capacity and voltage to operate the electrical apparatus. The first power-supplying cell arranged in the battery card includes two first planar attaching media respectively attaching thereto a first cathode material and a first anode material, and a first planar separator separating the first attaching media on the one hand and communicating the two first attaching media with each other on the other hand. The second power-supplying cell arranged in the battery card also includes two second planar attaching media respectively attaching thereto a second cathode material and a second anode material, and a second planar separator separating the second attaching media on the one hand and communicating the second attaching media with each other on the other hand. There is a housing housing therein the first and the second power-supplying cells to foπn the battery card having a weight energy density larger than 40 watt-hours/kilograms and a volume energy density larger than 100 watt-hours/liter. In addition, two contacts are mounted on the housing and respectively electrically connected to the first and the second power-supplying cells for power-supplying the electrical apparatus therethrough. In accordance with one aspect of the present invention, the battery card preferably has a weight energy density larger than 80 watt- hours/kilograms and a volume energy density larger than 200 watt- hours/liter. Preferably the electrical apparatus is a portable information appliance. Preferably the housing has a major square plane, and more preferably the plane has either one of sides thereof shorter than 10cm. Alternatively, the housing is substantially a parallelepiped having a thickness smaller than 1.5cm, and preferably less than 1cm. Preferably the parallelepiped has either one of sides thereof smaller than 15cm. Preferably the battery card is rechargeable, and more preferably the battery card is rechargeable in the electrical apparatus or through an external charger. In accordance with another aspect of the present invention, the battery card ftirther electrically connects therein a protection circuit for safeguarding the battery card from working at a voltage greater or lower than a specific value. In accordance with another aspect of the present invention, the battery card further electrically connects therein a fuel gauge for showing how much capacity said battery card keeps. In accordance with another aspect of the present invention, the battery card ftirther electrically connects therein a capacity display for displaying a capacity of the battery card. Preferably the housing is made of one of ABS (Acrylonitrile- Butadiene-Styrene resin) and manganese-aluminum alloy. In accordance with another aspect of the present invention, the battery card ftirther includes 7 power-supplying cells wherein the 9 power-supplying cells are divided into 3 parallelly connected groups each of which includes 3 serially connected power-supplying cells. In accordance with another aspect of the present invention, the battery card ftirther electrically connects therein a recharging circuit for enabling the battery card to be recharged thereby. Preferably two contacts are shielded from exposure until inserted into the electrical apparatus. Certainly, two first planar attaching media and two second planar attaching media are rigid. In according with another aspect of the present invention, the battery card ftirther includes a first casing housing therein the first power- supplying cell, and a second casing housing therein the second power- supplying cell electrically connected to the first power-supplying cell in series. It is ftirther another object of the present invention to provide a battery card adapted to be used with an electrical apparatus to be power- supplied by the battery card. The battery card contains several power- supplying cells (at least one power-supplying cell) in series and/or in parallel arrangement, making the desired capacity and voltage to operate the electrical apparatus. The first power-supplying cell ananged in the battery card includes two first attaching media respectively attaching thereto a first cathode material and a first anode material, a first separator separating the first attaching media on the one hand and communicating the two first attaching media with each other on the other hand, and a first casing housing therein the first power-supplying cell. The second power- supplying cell ananged in the battery card also includes two second attaching media respectively attaching thereto a second cathode material and a second anode material, a second separator separating the second attaching media on the one hand and communicating the second attaching media with each other on the other hand, and a second casing housing therein the second power-supplying cell. There is a housing having a thickness smaller than 1.5cm and housing therein the first and the second casings to form the battery card having a weight energy density larger than 40 watt-hours/kilograms and a volume energy density larger than 100 watt-hours/liter. In addition, there are two contacts mounted on the housing and respectively electrically connected to the first and the second power-supplying cells for power-supplying the electrical apparatus therethrough. Preferably the attaching media and the separators are windable into being cylindrically shaped. Alternatively, the attaching media and the separators are windable into being prismatically shaped. Preferably the housing is substantially a parallelepiped having a dimension smaller than 15cm, and more preferably smaller than 10cm. Preferably the first and second power-supplying cells are electrically connected in series. Preferably the thickness of the battery card is smaller than I cm. Preferably the battery card has an overall weight smaller than I80g, and more preferably smaller than 150g. Certainly, the attaching media respectively attach on two opposite side surfaces thereof the cathode material and the anode material. It is yet another object of the present invention to provide a battery card assembly which is adapted to be used with an electrical apparatus to be power-supplied by a battery card contained in the battery card assembly. According to the present invention, the electrical apparatus has a casing having a slot for mounting therein the battery card assembly. The battery card assembly includes an assembly body insertable into the slot of the electrical apparatus and having a card slit for replaceably inserting therein the battery card, and a retaining mechanism mounted in the assembly body for keeping the battery card in the card slit for power- supplying the electrical apparatus in a first instance and disengaging the battery card from the card slit out of the assembly body in a second instance. In accordance with one aspect of the present invention, the battery card assembly further includes a guiding mechanism for guiding the battery card to be inserted into the card slit. Preferably the guiding mechanism includes two opposite guiding side rails mounted in the assembly body In accordance with another aspect of the present invention, the batteiy card assembly ftirther includes a movable door for closing the card slit, and an elastic member for always closing the movable door against the card slit. Preferably the retaining mechanism includes an actuating button which protnides beyond the casing in the first instance and generally remains flush with the casing in the second instance. Certainly, the battery card has two power contacts and the assembly body includes a power receiving medium being electrically connected to the two power contacts of the battery card for receiving theretlirough a power from the battery card. Preferably the power receiving medium includes two conductors for respectively being electrically connected to the two power contacts of the batten.' card, and the assembly body includes a power cord electrically connected to the two conductors and having a terminal connector. Preferably the assembly body ftirther includes another card slit for inserting therein another battery card. Preferably the battery cards are of the same dimension. Alternatively, the battery cards are of different dimensions. Preferably the card slits are of the same size. Alternatively, the card slits are of different sizes. In accordance with another aspect of the present invention, the battery card assembly electrically connects therein a control circuit controlling from which batteiy card the electrical apparatus should be power-supplied. Preferably the control circuit includes diode switches, charger/protection circuit, fuel gauge circuit, and LED display circuit. Preferably the battery card assembly electrically connects therein a capacity detector for detecting how much capacity the battery cards keep. In accordance with another aspect of the present invention, the battery card assembly ftirther electrically connects therein a power shortage warner which will signal when either one of the battery cards nearly nms short of capacity. In accordance with another aspect of the present invention, the battery card assembly ftirther includes a display electrically connected to the power shortage warner for showing that one battery card nearly nms short of capacity. It is still ftirther another object of the present invention to provide a batteiy card assembly adapted to be used with an electrical apparatus to be power-supplied by a battery card contained in the battery card assembly. The battery card assembly includes an assembly body electrically connected to the electrical apparatus and having a card slit for replaceably inserting therein the battery card, and a retaining mechanism mounted in the assembly body for keeping the battery card in the card slit for power-supplying the electrical apparatus in a first instance and disengaging the battery card from the card slit out of the assembly body in a second instance. It is still ftirther another object of the present invention to provide a battery card assembly adapted to be used with an electrical apparatus, in which the electrical apparatus has a casing having a slot for mounting therein the battery card assembly, to be power-supplied by a battery card contained in the battery card assembly. The battery card assembly includes an assembly body insertable into the slot of the electrical apparatus and having a card slit for replaceably inserting therein the battery card. In accordance with one aspect of the present invention, the battery card preferably has a weight energy density larger than 40 watt- hours/kilograms and a volume energy density larger than 100 watt- hours/liter. More preferably, the battery card has the weight energy density larger than 80 watt-hours/kilograms and the volume energy density larger than 200 watt-hours/liter. Preferably the battery card has a thickness smaller than 1.5cm. and more preferably smaller than 1cm. It is still ftirther another object of the present invention to provide a battery card assembly adapted to be used with an electrical apparatus to be power-supplied by a battery card contained in the battery card assembly. The battery card assembly includes an assembly body electrically connected to the electrical apparams and having a card slit for replaceably inserting therein the battery card. It is still ftirther another object of the present invention to provide an electrical apparatus having a casing having a slot for mounting therein a battery card assembly having an assembly body having a card slit for replaceably inserting therein a battery card for power-supplying the electrical apparatus. In accordance with one aspect of the present invention, the battery card preferably has a weight energy density larger than 40 watt- hours/kilograms and a volume energy density larger than 100 watt- hours/liter, and more preferably the battery card has a weight energy density larger than 80 watt-hours/kilograms and a volume energy density larger than 200 watt-hours/liter. Preferably the battery card has a thickness smaller than 1.5cm, and more preferably smaller than 1 cm. Preferably battery card is substantially a parallelepiped having a dimension smaller than 15cm, and more preferably smaller than 10cm. It is still ftirther another object of the present invention to provide an electrical apparatus includes a casing having a card slit, and a battery card replaceably insertable into the card slit for power-supplying the electrical apparatus. The battery card includes two first planar attaching media respectively attaching thereto a first cathode material and a first anode material, a first planar separator separating the first attaching media on the one hand and communicating the two first attaching media with each other on the other hand to foπn a first power-supplying cell, two second planar attaching media respectively attaching thereto a second cathode material and a second anode material, a second planar separator separating the second attaching media on the one hand and communicating the second attaching media with each other on the other hand to form a second power-supplying cell electrically connected to the first power-supplying cell in series, a housing housing therein the first and the second power-supplying cells to form the battery card having a weight energy density larger than 40 watt-hours/kilograms and a volume energy density larger than 100 watt-hours/liter, and two contacts mounted on the housing and respectively electrically connected to the first and the second power-supplying cells for power-supplying the electrical apparatus theretlirough. In accordance with one aspect of the present invention, the battery card preferably has a weight energy density larger than 80 watt- hours/kilograms and a volume energy density larger than 200 watt- hours/liter. Preferably the housing is substantially a parallelepiped having a dimension smaller than 15cm, and more preferably smaller than 10cm. Preferably the housing has a thickness smaller than 1.5cm, and more preferably smaller than 1cm. Preferably the casing of the electrical apparatus ftirther includes a slot, and the electrical apparatus ftirther includes a battery card assembly slidably inserted into the slot and having the card slit. It is still ftirther another object of the present invention to provide an electrical apparatus includes a casing having a card slit and a battery card replaceably insertable into the card slit for power-supplying the electrical apparatus. The battery card includes two first attaching media respectively attaching thereto a first cathode material and a first anode material, a first separator separating the first attaching media on the one hand and communicating the two first attaching media with each other on the other hand to foπn a first power-supplying cell, a first casing housing therein the first power-supplying cell, two second attaching media respectively attaching thereto a second cathode material and a second anode material, a second separator separating the second attaching media on the one hand and communicating the second attaching media with each other on the other hand to form a second power-supplying cell electrically connected to the first power-supplying cell, a second casing housing therein the second power-supplying cell, a housing having a thickness smaller than 1.5cm and housing therein the first and the second casings to form the battery card having a weight energy density larger than 40 watt- hours/kilograms and a volume energy density larger than 100 watt- hours/liter, and two contacts mounted on the housing and respectively electrically connected to the first and the second pqwer-supp lying cells for power-supplying the electrical apparatus theretlirough. Preferably the thickness of the battery card is smaller than 1cm. Preferably the battery card has a weight energy density larger than 80 watt-hours/kilograms and a volume energy density larger than 200 watt- hours/liter. Preferably housing is substantially a parallelepiped having a dimension smaller than 15cm, and more preferably smaller than 10cm. Preferably the first and second power-supplying cells are electrically connected in series. Preferably the casing of the electrical apparatus ftirther includes a slot, and the electrical apparatus ftirther mc hides a battery card assembly slidablv inserted into the slot and having the card slit. It is still further another object of the present invention to provide an electrical apparatus includes a casing having a slot, a battery card assembly slidably insertable into the slot and having an assembly body having a card slit, and a battery card replaceably inserted into the card slit for power-supplying the electrical apparatus. The battery card has a thickness smaller than 1.5cm, a weight energy density larger than 40 watt- hours/kilograms, and a volume energy density larger than 100 watt- ours/liter. Preferably the battery card is substantially a parallelepiped having a thickness smaller than 1cm. Preferably the battery card has a weight energy density larger than 80 watt-hours/kilograms and a volume energy density larger than 200 watt- hours/liter. Preferably the battery card is rechargeable and the electrical apparatus ftirther includes a charger for recharging the battery card. Preferably the electrical apparatus ftirther includes a power buffer so that the power buffer will assume the work for power-supplying the electrical apparatus when the battery card nms short of capacity. Preferably the battery card assembly further includes another card slit for replaceably inserting therein another battery card. Preferably the electrical apparatus electrically connects thereto a power control circuit for controlling from which one of the battery cards the electrical apparatus should be power-supplied. Preferably the battery card assembly is formed into a cartridge, and the electrical apparatus ftirther includes a display for warning a user that one of the battery cards nms short of capacity. The present invention may best be understood through the following descriptions with reference to the accompanying drawings, in which: BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a cross-section view of a conventional battery cell in cylindrical stnictiire; Fig. 2 is a cross-section view of a conventional battery cell in prismatic stnictiire; Fig. 3 is a conventional battery pack for notebook computer containing cylindrical battery cells; Fig. 4 is a conventional battery pack for notebook computer containing prismatic battery cells; Fig. 5 is a cross-section view of a polymeric battery cell in flat shape; Fig. 6 is a cross-section view of a prefened battery card embodiment containing several battery cells in floppy disk size; Fig. 7 shows the battery recharging/protection circuit and the connection thereof to a battery card with a series of battery cells; Fig. 8 shows a block diagram of fuel gauge circuit embedded in battery card; Fig. 9 shows a batterv card with shutter closed when not in use; Fig. 10 shows a battery card with shutter open when inserted into the cartridge; Fig. 1 1 shows a cartridge with elastic door closed without battery card insertion; Fig. 12 shows a cartridge with elastic door open with battery card insertion; Fig. 13 shows a cartridge with two card slits for inserting therein two batterv cards; Fig. 14A shows a cartridge electrically connected to a notebook computer by a cable when in use; Fig. 14B shows a cartridge directly connected to a notebook computer when in use; and Fig. 15 shows a block diagram of the control circuit in an appliance with two batteiy cards. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The present invention is a battery power supply system consisting of battery card, battery card assembly where battery card slots in, and charger where battery card gets recharged. Battery cards are designed easy to carry, to store, and to exchange. Battery card assembly is a standard component in portable infoπnation appliances that receives battery card or battery cards in fixed foπnats. Charger is an accessory for safely recharging multiple battery cards with state-of-the-art charging algorithm. The battery card of the present invention is adapted to be used with an electrical apparatus to be power-supplied by the battery card. Preferably, the electrical apparatus is a portable information appliance. The battery card of the present invention contains several battery cells (at least one battery cell) in series and/or in parallel anangement, making the desired capacity and voltage to operate the electrical apparatus. Battery cells ananged in the battery card can be of any configuration, cylindrical or prismatic, as long as the geometry agrees with the card dimension after cells coupling. Recently developed polymeric battery cell in flat shape is another choice of battery cell in battery card. Fig. 5 shows a cross- section view of a polymeric battery cell in flat shape. As shown in Fig. 5, attaching media 51 with anode layer 52 and attaching media 53 with cathode layer 54 are dissociated by a separator 55. Layers are laminated with a matrix of polymer materials, and sealed in a flat casing 56. However, the amount of the battery cell contained in a battery card should not be limited. Fig. 6 shows a cross-section view of a prefened battery card embodiment containing several battery cells in floppy disk size. As shown in Fig. 6, the battery card 6 contains nine polymeric battery cells 601-609 in floppy disk size, each of which has a stnictiire as that of the polymeric battery cell 5 shown in Fig. 5. The first battery cell 601 includes two first planar attaching media respectively attaching thereto the first cathode material and the first anode material, and a first planar separator separating the first attaching media on the one hand and communicating the two first attaching media with each other on the other hand. The second battery cell 602 also includes two second planar attaching media respectively attaching thereto a second cathode material and a second anode material, and a second planar separator separating the second attaching media on the one hand and communicating the second attaching media with each other on the other hand. In Fig. 6 battery cells 601, 602, and 603 are connected in parallel, forming a group cell 610 sealed in an internal casing 61 1. Battery cells 604, 605, and 606 are connected in parallel, foπning a group cell 612 sealed in an internal casing 613. Battery cells 607, 608, and 609 are connected in parallel, foπning a group cell 614 sealed in an internal casing 615. Group cells 610, 612, and 614 are further connected in series to foπn a final battery card 6 sealed in a housing 616. In addition, there are two contacts (617 and 618) mounted on the housing 616 and electrically connected to batteiy cells 601-609 for power-supplying the electrical apparatus theretlirough. Therefore, the battery card 6 can be O 01/06580 wired to a battery card cartridge (not shown) through positive and negative terminals (617 and 618). Preferably the two contacts (617 and 618) are designed to be shielded from exposure until inserted into the electrical apparatus. The battery card of the present invention has a weight energy density larger than 40 watt-hours/kilograms and a volume energy density larger than 100 watt-hours/Iiter. Preferably, the battery card has a weight engery density larger than 80 watt-hours/kilograms and a volume energy density larger than 200 watt-hours/Iiter. The housing of the battery card has a major square plane. Preferably the plane has either one of sides thereof shorter than 10 cm. Alternatively, the housing of the battery card is substantially a paralleleiped having a thickness smaller than 1.5 cm, and more preferably less than 1 cm. The parallelepiped has either one of sides thereof smaller than 15 cm, preferably less than 10cm. However, the shape of the housing should not be limited. In addition, the battery card has an overall weight smaller than 180g, and preferably smaller than 150g. The battery card of the present invention contains battery cells in a plastic and/or metal alloy housing. Housing materials are light, thin, fiπn, cnis resistant, and good for heat dissipation. ABS (Acrylonitrile- Butadiene-Styrene resin) and magnesium-aluminum alloy are ciurent choices. Battery cells in the battery card of the present invention can be of any renewable battery chemistry, nickel metal hydride (NiMH), lithium-ion (Li-ion), zinc air, and/or other electrochemical system to be developed. Batteiy cells are coupled inside the battery card in series and/or in parallel anangement, making desired capacity and voltage to operate the appliances. The battery card of the present invention is recharagable. The battery card electrically connects therein a recharging circuit for enabling the battery card to be recharged thereby. Therefore, the battery card can be recharged by an independent charger outside the appliance, by connection to charger within the electrical apparatus, or by connection to wall power jack for direct charge from AC power supply. In addition, the battery card contains protection circuit for safeguarding the battery card from working at a voltage greater or lower than a specific value (i.e. prevent battery cells from being overcharged and/or over discharged). Fig. 7 shows a block diagram of a battery recharging/protection circuit 71 connected to a batteiy card 72 containing four battery cells in series. Inputs (B4, B3, B2, and B l ) in the recharging/protection circuit 71 are connected to conesponding positive teπninals of battery cells in battery card 72. Input BO is connected to the negative teπninal 73 of the battery card 72. A selector (not shown) in the recharging/protection circuit 71 is able to select combination of B0-B4 to examine voltage of any individual battery cell in the battery card 72. The negative teπninal 73 is connected to transistors 74 and 75, then to ground teπninal 76. Ground teπninal 76 connects to the GND input in the rechargingφrotection circuit 71. The gate of transistor 74 is connected to the DC output, associated with a discharge operation, of the recharging/protection device 71. The gate of transistor 75 is connected to the CC output, associated with a charging operation, of the recharging/protection circuit 71. Battery cards of the present invention are embedded with a fuel gauge circuit for detecting battery capacity and showing how much capacity the battery card keeps. The battery card includes a capacity display for displaying the capacity of the battery card. Fig. 8 shows a block diagram of the fuel gauge connection, wherein fuel gauge circuit 81 is embedded in the battery card 82. The fuel gauge circuit 81 is connected to battery cells 83 and the serial communication port (DQ). The fuel gauge circuit 81 contains light emitting diode anay 84 that displays detected information. In demonstration there are five segments of display connected to six terminals and a common output. Fig. 9 shows a basic design of the battery card. The battery card 9 includes a housing 91 made of upper shell 92 and lower shell 93. Along the surface there are tracking rails 94 that match the battery card to a cartridge (not shown) where the battery card solts in. A shutter 95 is provided on the front peripheral edge 96 of the housing 91 to cover the access 97, which contains "-*-" and "- * ' power outputs, when not in use. Fig. 10 shows when battery card 9 is inserted into the cartridge, .the shutter 95 moves to the other side exposing the access 97, which contains "- " " and "-" power outputs, to cartridge teπninal. EMBODIMENTS OF BATTERY CARD 1. A battery card made of cylindrical battery cells (less prefened) A battery card consists of three cylindrical Li-ion battery cells coupled in series. Each battery cell operates at 3.6V with a full capacity of 1.35Alι. Battery cell sizes 18mm in diameter. 65mm in heiglit, and weighs 42g. The battery card sizes 54(W) x 65(L) x 18(T) mm. and weighs 126g before circuit and case finish. The battery card delivers 14.6Wh ( 10.8V x 1.35A1 , good for operating a Pentium 300 notebook computer for 60 minutes. Pentium 300 notebook computer for 66 minutes. 5. A battery card made of A4 size polymeric battery cells (more prefened) A battery card in A4 size consists of three polymeric Li-ion battery cells in series. Each batteiy cell operates at 3.6V with a full capacity of 3.7Alι. Batterv cell sizes 280(W) x 210(L) x 0.75(T) mm, and weighs 1 lOg. The battery card sizes 280(W) x 210(L) x 2.4(T) mm, and weighs 330g before circuit and case finish. The battery card delivers 40Wh ( 10.8V x 3.7 All), good for operating a Pentium 300 notebook computer for 163 minutes. The battery card assembly of the present invention is adapted to be used with an electrical apparatus, in which the electrical apparatus has a casing having a slot for mounting therein the battery card assembly, to be power-supplied by a battery card contained in the battery card assembly. The battery card assembly includes an assembly body insertable into the slot of the electrical apparatus and having a card slit for replaceably inserting therein the battery card, and a retaining mechanism mounted in the assembly body for keeping the battery card in the card slit for power- supplying the electrical apparatus in a first instance and disengaging the battery card from the card slit out of the assembly body in a second instance. Battery card assembly is the host inside the electrical apparatus that receives one battery card or multiple battery cards. Battery card assembly can be foπned into a PC card cartridge when battery cards designed in PCMCIA specification. Fig. 1 1 shows a schematic diagram of a cartridge according to the present invention. Battery cartridge 1 1 , if independently 23 2. A battery card made of prismatic battery cells (less prefened) A battery card consists of three prismatic Li-ion battery cells coupled in series. Each battery cell operates at 3.6V with a full capacity of 0.95AIi. Battery cell sizes 34(W) x 48(L) x 9(T) mm, and weighs 40g. The battery card sizes 102(W) x 48(L) x 9(T) mm, and weighs 120g before circuit and case finish. The battery card delivers 10.3Wh ( 10.8V x 0.95Alι), good for operating a Pentium 300 notebook computer for 42 minutes. 3. A battery card made of credit card size polymeric battery cells (more prefened) A battery card in credit card size consists of four polymeric Li-ion battery cells in parallel. Each battery cell operates at 3.6V with a full capacity of 0.3Alι. Battery cell sizes 85(W) x 55(L) x 0.75(T) mm, and weighs 9g. The battery card sizes 85(W) x 55(L) x 3.2(T) mm, and weighs 36g before circuit and case finish. The battery card delivers 4.32Wh (3.6V x l .2Alι), good for operating a GSM cellular handset longer than 40 hours of talk time and/or 150 hours of standby. 4. A battery card made of floppy disk size polymeric battery cells (more prefened) A battery card in floppy disk size consists of nine polymeric Li-ion battery cells, three in series and three in parallel. Each battery cell operates at 3.6V with a full capacity of 0.5Alι. Battery cell sizes 90(W) x 90(L) x 0.75(T) mm, and weighs 15g. The battery card sizes 90(W) x 90(L) x 7.4(T) mm, and weighs I 35g before circuit and case finish. The battery card delivers 16.2Wlι ( 10.8V x 1.5Ah), good for operating a 22 designed, has a bottom half shell 1 1 1 and a top half shell 1 12 joined together. The cartridge 1 1 has front .1 13, back 1 14, side surfaces 1 15, 1 16, and substantially planar surfaces on the top 1 17 and in the bottom 1 18. In addition, the cartridge 1 1 ftirther includes a guiding mechanism (not shown) for guiding the battery card to be inserted into the card slit. The guiding mechanism of the cartridge 1 1 includes two opposite guiding side rails (not shown) mounted in the assemly body. Moreover, the cartridge 1 1 includes a moveable door 1 19 for enclosing the card slit, and an elastic member (not shown) for always closing the moveable door against the card slit. In Fig. 1 1, the movable door 1 19 closes and the actuating button 1 10 is down when there is no battery card in the cartridge 1 1. In Fig. 12, the movable door 1 19 opens with an up actuating button 1 10 when battery card inserts. When the user wants to change the battery card, he can simply push actuating button 1 10 down to open moveable door 1 19 to release battery card. In addition, the cartridge 1 1 includes two conductors (not shown) being electrically connected to the two power contacts of the battery card for receiving theretlirough a power from the battery card when the battery card solts in. The cartridge 1 1 ftirther includes a power cord (not shown) electrically connected to the two conductors and having a teπninal connector (not shown). Alternatively, the cartridge can be designed to have another card slit for inserting therein another battery card. Fig. 13 shows a cartridge 13 with two card slits ( 131 and 132) for inserting therein two battery cards. Certainly, those card slits ( 13 1 and 132) can be designed to have same size or different sizes. Conespondingly, the battery card can be of the same dimension or different dimensions. Certainly, in another embodiment, the battery card assembly can be an independent cartridge outside the electrical apparatus As shown m Fig 14 A, the cartridge 14 with two card slits ( 141 and 142) can be electrically connected to the notebook computer 143 by a cable 144 when in use Alternatively, the cartridge 14 with two card slits ( 141 and 142) can be directly connected to the notebook computei 143 as shown in Fig 14B In the case of using single battery card, the cartridge electrically connects to a power buffer (not shown) in the electrical apparatus when the battery card nms short of the capacity Changing power connection between the battery card and the power buffer, i e , a bridge battery and/or a capacitor, by a diode switch, the user can change their battery card at a certain time interval without turning off the electncal apparatus when the battery card nm short of the capacity In the case of using multiple battery cards, the cartridge connects power to the electrical apparatus from only one of the battery card at any given time Until the first battery card is completely discharged, the cartridge automatically switches the first battery card to another battery card without disturbing the device operation By changing power connection between battery cards and taking power from only one battery card at any given time, the user can change battery card without turning off the electrical apparatus when one of the battery card nm short of capacity Therefore, in both cases the appliance operation will not be internipted when the battery card is nm short of the capacity In addition, the battery card assembly can be designed to electrically connect therein a capacity detector for detecting how much capacity the battery cards keep, and a power shortage warner which will signal when either one of the battery card nearly nms short of capacity Certainly, battery card assembly can also be designed to have a display electrically connected to the power shortage warner for warning a user that one of the battery cards nms short of capacity. Fig. 15 shows a block diagram of a control circuit in an appliance with two batterv cards. A first battery card 151 is connected via a diode 152, which is positioned in the forward direction, to the input tenninal of a DC/DC converter 153 that supplies power to the computer. A second battery card 154 is connected to the input teπninal of the DC/DC converter 153 via a diode 155, which is also positioned in the forward direction. The first battery card 151 and the second battery card 154 are OR-connected via the diode 152 and diode 155 to the DC/DC converter 153. Power from either the first battery card 151 or the second battery card 154 is supplied to the computer via the diode 152 or the diode 155 and the DC/DC converter 153. An AC/DC adapter 156, which can also be the power buffer, is connected between the first battery card 151 and the diode 152 through a first charge switch 157, and is ftirther connected between the second battery card 154 and the diode 155 through a second charge switch 158. The AC/DC adapter or the power buffer 156 provides charging routes in addition to a power supply route to the appliance via the DC/DC converter 153. Either the first battery card 151 or the second battery card 154 is charged along the charging routes, and power can be supplied to appliance via either the diode 152 or the diode 155 and DC/DC converter 153. EMBODIMENTS OF BATTE Y CARD ASSEMBLY 1. A cartridge containing one battery card A cartridge containing one battery card is designed for being mounted in a slim and compact appliances. A diode switch connects to a power buffer, i.e., a bridge battery and/or a capacitor, when the battery card is disconnected from the cartridge. Users are able to change their battery card without turning off the machine within a certain period of time. 2. A cartridge containing more than one battery card A cartridge containing more than one battery card is designed for full function appliances. A diode switch connects to only one of the battery card at any given time. While user extracts the low-capacity battery card out of the cartridge, the cartridge switches to another battery card without disturbing the operation. User can insert a new battery card with full capacity anytime before the second battery card exhausts. However, number of battery card able to be installed in the cartridge should not be limited. This invention introduces a new battery power system that operates by battery packs in light, thin, safe, and user-friendly card configuration. As portability requires battery packs continue to shrink, solution to the shorter n time dilemma is to design a power system that provides non- interniptible energy by easy swapping unit battery packs in user-friendly foπnats. Instead of adding more power to appliance, the present invention brings a different pattern using battery cards to provide a minimum nm time that satisfies general applications whereas the system upholds power continuity. When battery cards are charged on a separate charger outside the appliance, issue of public safety can be minimized without adding any inconvenience to mobile users. With the present invention users carry no more power than they actually need. They no longer worry losing data when battery power exhausts. Furtheπnore, battery packs, in card shape can be standardized that makes interchangeability between appliances easy and possible According to the description with reference to the accompanying drawings, we can see that battery power system of the present invention improves the defect encountered by the prior arts. While the invention has been described in teπns of what are presently considered to be the most practical and prefened embodiments, it is to be understood that the invention need not be limited to the disclosed embodiment. On the contrary, it is intended to cover various modifications and similar anangements included within the spirit and scope of the appended claims which are to be accorded with the broadest inteφretation so as to encompass all such modifications and similar stnictures. Therefore, the above description and illustration should not be taken as limiting the scope of the present invention which is defined by the appended claims.

Claims: WHAT WE CLAIM IS: 1. A battery card adapted to be used with an electrical apparatus to be power-supplied by said battery card comprising: two first planar attaching media respectively attaching thereto a first cathode material and a first anode material; a first planar separator separating said first attaching media on the one hand and communicating said two first attaching media with each other on the other hand to form a first power-supplying cell; two second planar attaching media respectively attaching thereto a second cathode material and a second anode material; a second planar separator separating said second attaching media on the one hand and communicating said second attaching media with each other on the other hand to foπn a second power-supplying cell electrically connected to said first power-supplying cell; a housing housing therein said first and said second power-supplying cells to foπn said battery card having a weight energy density larger than 40 watt-hours/kilograms and a volume energy density larger than 100 watt- hours/Iiter; and two contacts mounted on said housing and respectively electrically connected to said first and said second power-supplying cells for power- supplying said electrical apparatus theretlirough. 2. A battery card according to claim 1 wherein said battery card preferably has said weight energy density larger than 80 watt- hours/kilograms and said volume energy density larger than 200 watt- hours/Iiter. 3. A battery card according to claim 1 wherein said electrical apparatus is portable. 4. A battery card according to claim 1 wherein said housing has a major square plane. 5. A battery card according to claim 4 wherein said plane has either one of sides thereof shorter than 10cm. 6. A battery card according to claim 1 wherein said housing generally is a parallelepiped. 7. A battery card according to claim 6 wherein said parallelepiped has a thickness smaller than 1.5cm. and more preferably less than 1cm. 8. A battery card according to claim 6 wherein said parallelepiped has either one of sides thereof smaller than 15cm. 9. A battery card according to claim 1 wherein said electrical apparatus is an infoπnation appliance. 10. A battery card according to claim 1 wherein said card is rechargeable. 1 1. A battery card according to claim 10 wherein said card is rechargeable in said electrical apparatus. 12. A battery card according to claim 10 wherein said card is rechargeable through an external charger. 13. A battery card according to claim 1, ftirther electrically connecting therein a protection circuit for safeguarding said battery card from working at a voltage greater or lower than a specific value. 14. A battery card according to claim I , ftirther electrically connecting therein a fuel gauge for showing how much capacity said battery card keeps. 15. A battery card according to claim 1. ftirther electrically connecting therein a capacity display for displaying a capacity of said battery card. 16. A battery card according to claim 1 wherein said housing is made of one of ABS (Acrylonitrile-Butadiene-Styrene resin) and manganese- aluminum alloy. 17. A battery card according to claim 1 , ftirther comprising 7 power- supplying cells wherein said 9 power-supplying cells are divided into 3 parallelly connected groups each of which includes 3 serially connected power-supplying cells. 18. A battery card according to claim I, further electrically connecting therein a recharging circuit enabling said battery card to be recharged thereby. 19. A battery card according to claim 1 wherein said two contacts are shielded from exposure until inserted into said electrical apparatus. 20. A battery card according to claim 1 wherein said two first planar attaching media and said two second planar attaching media are rigid. 21. A battery card according to claim 1, ftirther comprising: a first casing housing therein said first power-supplying cell; and a second casing housing therein said second power-supplying cell electrically connected to said first power-supplying cell in series. 22. A battery card adapted to be used with an electrical apparatus to be power-supplied by said battery card comprising: two first attaching media respectively attaching thereto a first cathode material and a first anode material; a first separator separating said first attaching media on the one hand and communicating said two first attaching media with each other on the other hand to foπn a first power-supplying cell; a first casing housing therein said first power-supplying cell; two second attaching media respectively attaching thereto a second cathode material and a second anode material; a second separator separating said second attaching media on the one hand and communicating said second attaching media with each other on the other hand to form a second power-supplying cell electrically connected to said first power-supplying cell; a second casing housing therein said second power-supplying cell; a housing having a thickness smaller than 1.5cm and housing therein said first and said second casings to foπn said battery card having a weight energy density larger than 40 watt-hours/kilograms and a volume energy density larger than 100 watt-hours/Iiter; and two contacts mounted on said housing and respectively electrically connected to said first and said second power-supplying cells for power- supplying said electrical apparatus theretlirough. 23. A battery card according to claim 22 wherein said attaching media and said separators are windable into being cylindrically shaped. 24. A battery card according to claim 22 wherein said attaching media and said separators are windable into being prismatically shaped. 25. A battery card according to claim 22 wherein said housing is substantially a parallelepiped. 26. A battery card according to claim 25 wherein said housing has a dimension smaller than 15cm, and preferably smaller than 10cm. 27. A battery card according to claim 22 wherein said first and second power-supplying cells are electrically connected in series. 28. A battery card according to claim 22 wherein said thickness is preferably smaller than 1cm. 29. A battery card according to claim 22 having an overall weight smaller than 180g, and preferably smaller than 150g. 30. A battery card according to claim 22 wherein said attaching media respectively attach on two opposite side surfaces thereof said cathode material and said anode material. 31. A battery card assembly adapted to be used with an electrical apparatus, in which said electrical apparatus has a casing having a slot for mounting therein said battery card assembly, to be power-supplied by a battery card contained in said battery card assembly comprising: an assembly body insertable into said slot of said electrical apparatus and having a card slit for replaceably inserting therein said battery card; and a retaining mechanism mounted in said assembly body for keeping said battery card in said card slit for power-supplying said electrical apparatus in a first instance and disengaging said battery card from said card slit out of said assembly body in a second instance. 32. A battery card assembly according to claim 31, ftirther comprising a guiding mechanism for guiding said battery card to be inserted into said card slit. 33. A battery card assembly according to claim 32 wherein said guiding mechanism includes two opposite guiding side rails mounted in said assembly body. 34. A battery card assembly according to claim 31 , ftirther comprising a movable door for closing said card slit. 35. A battery card assembly according to claim 34, ftirther comprising an elastic member for always closing said movable door against said card slit. 36. A battery card assembly according to claim 31 wherein said retaining mechanism includes an actuating button which protnides beyond said casing in said first instance and generally remains flush with said casing in said second instance. 37. A battery card assembly according to claim 31 wherein: said battery card has two power contacts; and said assembly body includes a power receiving medium for being electrically connected to said two power contacts for receiving theretlirough a power from said battery card. 38. A battery card assembly according to claim 37 wherein: said power receiving medium includes two conductors for respectively being electrically connected to said two power contacts; and said assembly body ftirther includes a power cord electrically connected to said two conductors and having a teπninal connector. 39. A battery card assembly according to claim 31 wherein said assembly body ftirther includes another card slit for inserting therein another battery card. 40. A battery card assembly according to claim 39 wherein said battery cards are of the same dimension. 41. A battery card assembly according to claim 39 wherein said battery cards are of different dimensions. 42. A battery card assembly according to claim 39 wherein said card slits are of the same size. 43. A battery card assembly according to claim 39 wherein said card slits are of different sizes. 44. A battery card assembly according to claim 39, electrically connecting therein a control circuit controlling from which battery card said electrical apparatus should be power-supplied. 45. A battery card assembly according to claim 44 wherein said control circuit includes diode switches, charger/protection circuit, fuel gauge circuit, and LED display circuit. 46. A batterv card assembly according to claim 39, electrically connecting therein a capacity detector for detecting how much capacity said battery cards keep. 47. A battery card assembly according to claim 39, electrically connecting therein a power shortage warner which will signal when either one of said battery cards nearly nms short of capacity. 48. A battery card assembly according to claim 47, ftirther comprising a display electrically connected to said power shortage warner for showing that said one battery card nearly nins short of capacity. 49. A battery card assembly adapted to be used with an electrical apparatus to be power-supplied by a battery card contained in said battery card assembly comprising: an assembly body electrically connected to said electrical apparatus and having a card slit for replaceably inserting therein said battery card; and a retaining mechanism mounted in said assembly body for keeping said battery card in said card slit for power-supplying said electrical apparatus in a first instance and disengaging said battery card from said card slit out of said assembly body in a second instance. 50. A battery card assembly adapted to be used with an electrical apparatus, in which said electrical apparatus has a casing having a slot for mounting therein said battery card assembly, to be power-supplied by a battery card contained in said battery card assembly comprising an assembly body insertable into said slot of said electrical apparatus and having a card slit for replaceably inserting therein said battery card. 51. A battery card assembly according to claim 50 wherein said battery card has a weight energy density larger than 40 watt-hours/kilograms and a volume energy density larger than 100 watt-hours/Iiter. 52. A battery card assembly according to claim 51 wherein said battery card preferably has said weight energy density larger than 80 watt- hours/kilograms and said volume energy density larger than 200 watt- hours/Iiter. 53. A battery card assembly according to claim 51 wherein said battery card has a thickness smaller than 1.5cm. 54. A battery card assembly according to claim 53 wherein said battery card preferably has a thickness smaller than 1.5cm, and more preferably smaller than 1cm. 55. A battery card assembly adapted to be used with an electrical apparatus to be power-supplied by a battery card contained in said battery card assembly comprising an assembly body electrically connected to said electrical apparatus and having a card slit for replaceably inserting therein said battery card. 56. An electrical apparatus having a casing having a slot for mounting therein a battery card assembly having an assembly body having a card slit for replaceably inserting therein a battery card for power-supplying said electrical apparatus. 57. An electrical apparatus according to claim 56 wherein said battery card has a weight energy density larger than 40 watt-hours/kilograms and a volume energy density larger than 100 watt-liours/liter. 58. An electrical apparatus according to claim 57 wherein said battery card preferably has said weight energy density larger than 80 watt- hours/kilograms and said volume energy density larger than 200 watt- hours/Iiter. 59. An electrical apparatus according to claim 56 wherein said battery card has a thickness smaller than 1.5cm. 60. An electrical apparatus according to claim 59 wherein said thickness preferably is smaller than I cm. 61. An electrical apparatus according to claim 56 wherein said battery card is substantially a parallelepiped and has a dimension smaller than 15cm. 62. An electrical apparatus according to claim 61 wherein said dimension preferably is smaller than 10cm. 63. An electrical apparatus comprising: a casing having a card slit; and a battery card replaceably insertable into said card slit for power- supplying said electrical apparatus and including: two first planar attaching media respectively attaching thereto a first cathode material and a first anode material; a first planar separator separating said first attaching media on the one hand and communicating said two first attaching media with each other on the other hand to foπn a first power-supplying cell; two second planar attaching media respectively attaching thereto a second cathode material and a second anode material; a second planar separator separating said second attaching media on the one hand and communicating said second attaching media with each other on the other hand to form a second power-supplying cell electrically connected to said first power-supplying cell in series; a housing housing therein said first and said second power-supplying cells to foπn said battery card having a weight energy density larger than 40 watt-hours/kilograms and a volume energy density larger than 100 watt- hours/liter; and two contacts mounted on said housing and respectively electrically connected to said first and said second power-supplying cells for power- supplying said electrical apparatus theretlirough. 64. An electrical apparatus according to claim 63 wherein said battery card has said weight energy density larger than 80 watt-hours/kilograms and said volume energy density larger than 200 watt-hours/liter. 65. An electrical apparatus according to claim 63 wherein said housing is generally a parallelepiped. 66. An electrical apparatus according to claim 65 wherein said housing has a dimension smaller than 15cm, and preferably smaller than 10cm. 67. An electrical apparatus according to claim 65 wherein said housing has a thickness smaller than 1.5cm, and preferably smaller than 1cm. 68. An electrical apparatus according to claim 63 wherein: said casing further includes a slot; and said electrical apparatus ftirther includes a battery card assembly slidably inserted into said slot and having said card slit. 69. An electrical apparatus comprising: a casing having a card slit; and a battery card replaceably insertable into said card slit for power- supplying said electrical apparatus and including: two first attaching media respectiveK- attaching thereto a first cathode material and a first anode material; a first separator separating said first attaching media on the one hand and communicating said two first attaching. media with each other on the other hand to foπn a first power-supplying cell; a first casing housing therein said first power-supplying cell; two second attaching media respectively attaching thereto a second cathode material and a second anode material; a second separator separating said second attaching media on the one hand and communicating said second attaching media with each other on the other hand to form a second power-supplying cell electrically connected to said first power-supplying cell; a second casing housing therein said second power-supplying cell; a housing having a thickness smaller than 1.5cm and housing therein said first and said second casings to foπn said battery card having a weight energy density larger than 40 watt-hours/kilograms and a volume energy density larger than 100 watt-hours/Iiter; and two contacts mounted on said housing and respectively electrically connected to said first and said second power-supplying cells for power- supplying said electrical apparatus theretlirough. 70. An electrical apparatus according to claim 69 wherein said thickness is * preferably smaller than 1cm. 71. An electrical apparatus according to claim 69 wherein said battery card has a weight energy density larger than 80 watt-hours/kilograms and said volume energy density larger than 200 watt-hours/Iiter. 72. An electrical apparatus according to claim 69 wherein said housing is substantially a parallelepiped having a dimension smaller than 15cm, and preferably smaller than 10cm. 73. An electrical apparatus according to claim 69 wherein said first and second power-supplying cells are electrically connected in series. 74. An electrical apparatus according to claim 69 wherein: said casing ftirther includes a slot; and said electrical apparatus ftirther includes a battery card assembly slidably inserted into said slot and having said card slit. 75. An electrical apparatus comprising: a casing having a slot; a battery card assembly slidably insertable into said slot and having an assembly body having a card slit; a battery card replaceably inserted into said card slit for power-supplying said electrical apparatus, having a thickness smaller than 1.5cm and having a weight energy density larger than 40 watt-hours/kilograms and a volume energy density larger than 100 watt-hours/Iiter. 76. An electrical apparatus according to claim 75 wherein said battery card is substantially a parallelepiped having said thickness preferably smaller than 1cm. 77. An electrical apparatus according to claim 75 wherein said battery card has said weight energy density larger than 80 watt-hours/kilograms and said volume energy density larger than 200 watt-hours/Iiter. 78. An electrical apparatus according to claim 75 wherein said battery card is rechargeable and said electrical apparatus ftirther includes a charger for recharging said battery card. 79. An electrical apparatus according to claim 75, ftirther comprising a power buffer so that said power buffer will assume the work for power- supplying said electrical apparatus when said battery card nms short of capacity. 80. An electrical apparatus according to claim 75 wherein said battery card assembly ftirther includes another card slit for replaceably inserting therein another battery card. 81. An electrical apparatus according to claim 80, electrically connecting thereto a power control circuit for controlling from which one of said battery cards said electrical apparatus should be power-supplied. 82. An electrical apparatus according to claim 80 wherein: said battery card assembly is foπned into a cartridge; and said electrical apparatus ftirther includes a display for warning a user that one of said battery cards nms short of capacity.

Inventors: CHAING CYRIL C K, REI MIN HON, CHAING, CYRIL, C., K., REI, MIN, HON
Applicants: CHAING CYRIL C K, REI MIN HON, CHAING, CYRIL, C., K., REI, MIN, HON
Application year: 1999
Main classification: H01M2
IPC codes: H01M2, H01M6, H01M10