Abstract:
An electric vehicle battery recharge-replacement system has four major parts: (1) a rechargeable battery pack consisting of a number of separate sub-packs with an identical dimension and energy capacity, (2) a same number of battery sub-pack compartments on an electric vehicle, and all sub-pack compartments having an identical dimension, (3) a recharging array consisting of a number of individual recharging compartments stacking together, and each recharging compartment having a dimension same as the vehicle sub-pack compartment, and (4) some battery sub-pack holding cases, each of which having an identical dimension. With this system, battery pack replacement can be realized by replacing drained battery sub-packs in an electric vehicle&#39;s compartments with recharged battery sub-packs in a recharging array&#39;s compartments. In this system, each battery sup-pack can further consist of two to four identical sub-sub-packs, which are even lighter and easier to handle.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority from U.S. Provisional Application Ser. No. 61/392,930 filed on Oct. 13, 2010, and the contents of which are incorporated herein by reference in its entirety. 
     
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
       [0002]    Not applicable. 
       FIELD OF THE INVENTION 
       [0003]    The present invention, in general, relates to electric vehicles, and more specifically, to a recharge-replacement system that realizes practical replacement of drained batteries on electric vehicles with recharged batteries at recharge-replacement stations. 
       BACKGROUND OF THE INVENTION 
       [0004]    Electric vehicles are drawing more and more attention from automobile manufacturers, the public and governments of many countries due to their low energy cost and low-to-zero direct or indirect emissions of various air pollutants. 
         [0005]    Advances in battery technology in recent years have significantly promoted development of electric vehicles. For example, a well-designed lithium-ion (Li-ion) battery pack has the capacity to power an electric vehicle (EV) for a 40-mile range, which covers about 80 percent of daily driving activities. A few automobile manufacturers have announced that they have planned to start mass production of EVs in early 2010s. Since the batteries are the only power source of electric vehicles, recharging drained batteries will become a routine task for EV drivers. It is generally anticipated that charging a battery on an electric vehicle may not be a problem for those vehicles that are parked in or beside residential parking garages since power outlets are readily accessible, even though running electric cables in a crowded garage may be a hassle if recharging work is performed on a daily basis. 
         [0006]    For those drivers who do not have an easy or convenient access to power outlets, there is a practical problem for them to charge their EV batteries. This is particularly true in urban areas where residents usually have to park their vehicles in open spaces along street curbs and in public-owned parking lots. Charging electric vehicles at those open spaces may have practical problems. For example, those open spaces may not be close enough to a resident dwelling, and leaving an electric vehicle at charging status without close attention may not safe and secure. Some EV manufacturers, battery-charging equipment suppliers, hotel and supermarket owners have been discussing options of setting up charging stations at the parking lots of urban hotels or supermarkets. However, not many people live near hotels and supermarkets. In addition, leaving their electric vehicles at charging stations away from their residences for an extended period of time may not be liked by EV drivers. Therefore, the challenge or the difficulty in recharging EV batteries may hinder wide sales of electric vehicles, in particular, in urban areas. 
         [0007]    Another potential solution for EV battery recharging problem is to build battery recharge-replacement stations, at which an EV driver can simply exchange his/her drained battery for a fully-charged battery which has been recharged at the station. This solution, if practical, would enable an EV driver to replenish his/her EV&#39;s power capacity fast, as fast as refilling a gasoline tank on a regular gasoline-powered vehicle. If an extensive network or infrastructure of such replacement stations could be built up, it could fully meet the recharging need of electric vehicles after mass production. However, some challenges exist. First, an EV battery, or more precisely an EV battery pack, usually has a relatively large volume and a heavy weight in order to hold a sufficient power capacity. Recent demonstrative replacement stations indicate that such stations need heavy equipment in structured facilities to perform battery pack replacement. Again, space availability remains a practical problem in urban areas. Secondly, construction of necessary facilities in replacement stations and installation of heavy equipment will need significant capital investments. Without heavy equipment and structured facilities, how to perform a quick replacement operation for the heavy battery packs will be a major challenge for either EV drivers or replacement stations. 
         [0008]    It is obvious that there exists an urgent need in the current art for a convenient and effective method for recharging and/or replacing EV batteries in the upcoming build-up of EV battery recharging infrastructure. 
       SUMMARY OF THE INVENTION AND ADVANTAGES 
       [0009]    The present invention aims at providing a practical system that enables electric vehicle (EV) drivers to obtain recharged batteries for their EVs whenever needed. In particular, the present invention provides a special method to dismember an EV battery pack into uniform sub-packs, creates uniform battery sub-pack holding cases for both EVs and recharging arrays, thus making replacement operation of EV battery sub-packs practically doable at recharge-replacement stations by either EV drivers or station staffs without help of heavy equipment. The entire system of the present invention is easy to implement, and is expected to effectively facilitate an extensive EV recharge-replacement network or infrastructure that is critically needed along with EV mass production. 
         [0010]    The present invention involves four major parts: (1) a number of individual battery sub-packs, each of which has an identical dimension and energy capacity, and the total capacity of all battery sub-packs can run an electric vehicle for a desirable driving range, (2) a same number of battery sub-pack compartments on an electric vehicle (hereafter referred to as sub-pack compartments), and all sub-pack compartments have an identical dimension, (3) a recharging array consisting of a number of individual recharging compartments, each of which has a dimension same as the vehicle sub-pack compartment, and (4) some battery sub-pack holding cases, each of which having an identical dimension. The number of battery sub-packs depends on battery design capacity and driving range of the EV. For example, based on the current Li-ion battery technologies and a 40-mile driving range originally powered by a 375-lb battery pack, five sub-packs can be designed and each sub-pack can be manufactured with a driving range of 8-mile and a weight about 75 pounds so that it can be moved manually by a strong adult. To further reduce the weight of each sub-pack, six battery sub-packs can be designed and used, and each sub-pack will have a weight about 60 pounds. In addition, each battery sup-pack can be manufactured by grouping together two to four identical sub-sub-packs (hereafter simplified as “ss-pack”). Each individual ss-pack will have a weight about ½ to ¼ of the sub-pack so that it can be handled by an adult more easily. It is anticipated that, with technology development of rechargeable batteries, the capacity and driving range of each sub-pack or ss-pack will increase, or the weight of those sub-pack or ss-pack will decrease. The following description of the present invention uses five battery sub-packs for demonstration and simplification purpose. 
         [0011]    The locations of five sub-pack compartments may vary, depending on EV models, available spaces on an EV and degree of easy access to those spaces. A preferred embodiment is to locate the first four vehicle compartments under driver&#39;s seat, left rear seat, passenger&#39;s seat, and right rear seat, respectively. Usually, there is a potential space of approximately 25×15×10-inch 3  under each of the above seats of an electric vehicle. Therefore, as long the battery sub-pack holding case (see next paragraph) is smaller than this potential space but large enough to accommodate a battery sub-pack, this potential space can be explored for a solid and strong battery sub-pack compartment. The compartments at those locations are easy to access, and well protected from theft and rainfall because they can be covered and locked instantaneously when the vehicle doors are closed and locked. Another sub-pack compartment (i.e., the fifth compartment) can be located in the rear truck. This location is also safe from theft and rain since it is covered and locked when the trunk is locked. Within each vehicle sub-pack compartment, a sub-pack holding case (hereafter referred to as vehicle battery sub-pack holding case or simply as sub-pack holding case) is installed on a pair of sliding rulers so that the sub-pack case can slide easily into and out from the compartment sideways. 
         [0012]    For a recharging array, several recharging compartments can be stacked together or in a matrix form. Within each recharging compartment of the recharging array, a sub-pack recharging case (or simply referred to as recharging case) with a dimension same as the vehicle sub-pack holding case is installed on a pair of sliding rulers so that the recharging case can slide into and out from the recharging compartment easily and quickly. 
         [0013]    An EV battery sub-pack can be installed in the sub-pack holding case or the sub-pack recharging case with necessary fastening devices and functional connections in either a sub-pack compartment on an EV or a recharging compartment of a recharging array. With such an arrangement, the heavy battery pack is dismembered and handled as five separate individual sub-packs, each of which can be further handled by handling two or four much lighter ss-packs individually. 
         [0014]    Power delivery from individual sub-packs on an EV is operated automatically or manually through an on-vehicle sub-pack control panel that is located in a convenient location for the EV driver. The control panel also displays capacity status of each sub-pack. For a recharging array, sub-pack recharging is managed automatically or manually through the array&#39;s control panel, which is located on a convenient location on the recharging stack or matrix. 
         [0015]    For one recharge-replacement station, one or several recharging arrays may be deployed, depending on demands on EV battery recharging in the surrounding areas. It will be desirable to build a recharge-replacement station at an existing gasoline station and to deploy a recharging array or arrays in locations convenient for EV drivers. Such arrangements will save land, reduce capital investments, promote effective management and lower maintenance cost, thus leading to lower battery charging fees. 
         [0016]    When an electric vehicle runs, the driver decides, according to sub-pack capacity information being updated continuously and displayed on the sub-pack control panel, when to replace the battery sub-packs. When a replacement decision is made, the driver drives the EV into the nearest recharge-replacement station, stops the vehicle by a recharging array, opens a vehicle sub-pack compartment, pulls the sub-pack holding case with the drained sub-pack out from the sub-pack compartment, disengages all fastening devices and functional connections, and then removes the drained sub-pack from the holding case. The empty sub-pack holding case is now ready for a newly-charged sub-pack. The driver uses the same procedure to obtain a fully-charged sub-pack from one recharging compartment in the recharging array. The driver then installs the new sub-pack into the EV sub-pack holding case, engages all fastening devices and functional connections, pushes the holding case into the sub-pack compartment and closes the compartment door. The driver uses the same procedure to install the drained sub-pack pack into the recharging case and pushes the recharging case back into the recharging compartment. Recharging of the drained sub-pack in the recharging compartment can be then started either automatically or manually, or by a pre-set schedule for off-peak charging. The EV driver then follows the same steps to replace other drained sub-packs on the EV. 
         [0017]    The present invention converts handling of a heavy battery pack into handling individual sub-packs. By dismembering a single, bulky and heavy battery pack into five separate sub-packs, each of which may be further dismembered into two to four individual ss-packs, the only weight-lifting task in replacement operation is unloading or loading the much lighter sub-packs or ss-packs from or into EV&#39;s sub-pack holding cases or the recharging array&#39;s recharging cases. Transporting of the battery sub-pack between the EV and the recharging array can be performed with the help of a wheeled cart. It is further preferred that the replacement process be managed by a station staff member, with a reasonable service fee to be added to the sub-pack recharge-replacement fee. A serviced replacement is likely to shorten the replacement process, to avoid some operational errors, and to be even necessary sometimes for some physically-weak drivers. 
         [0018]    The advantages of the present invention are obvious. First, the much smaller battery sub-packs (or ss-packs) are much easier to manufacture, transport and install. The dismemberment of a huge battery pack into several sub-packs provides EV manufacturers flexibility in locating the battery sub-packs in the EV bodies. 
         [0019]    Secondly, the present invention makes it possible to standardize battery sub-packs for universal use on many, if not all, models of passenger EVs. Small compact EVs can use three to four standardized battery sub-packs, while medium or luxurious sedans can use five to six standardized battery sub-packs. In practice, it may need to make two types of standardized battery sub-packs, one smaller type and one bigger type. The smaller type is for small EVs since their bodies are small, and the bigger type is for bigger EVs since their bodies are bigger. It can be expected that when one type, or two types, of standardized battery sub-packs can be used by many EV manufacturers, the economy of scale will function significantly in battery manufacturing, thus reducing the cost of battery sub-packs significantly. In addition, standardization of battery sub-packs will enable battery recharge-replacement stations to charge and store only one or two types of sub-packs, solving a critical problem of battery replacement practice. 
         [0020]    Thirdly, the uniform dimension of the battery sub-pack cases for both EV&#39;s sub-pack compartment and recharging array&#39;s recharging compartment makes it practically feasible to exchange drained and recharged batteries at a recharge-replacement station. More specifically, the uniform sub-pack cases and associated sliding mechanism make it much easier for either EV drivers or station staffs to remove or install a battery sub-pack from or into both electric vehicles and recharging arrays at a recharge-replacement station. 
         [0021]    Further, the EV owners will no longer need to charge their EV batteries at home, or at charging stations away from homes, nor will they need to wait for extended period of time for recharging drained battery packs. To be free from the recharging burden is extremely important for urban residents, and will promote a wide acceptance and usage of electric vehicles, and therefore promoting energy conservation and environmental protection. 
         [0022]    Further, the recharging array can be conveniently installed at many existing gasoline stations in parallel to gasoline dispensers. Therefore, additional land and space for battery recharge-replacement activities will be minimized. With such arrangement, an EV owner can replace the battery, and at the same time refill the gasoline tank when necessary if such a tank is installed for an electricity-generating engine on the vehicle. Considering the existence of vast infrastructures of gasoline stations throughout many countries, the present invention will help build up very quickly extensive and convenient networks of recharge-replacement stations in many countries. 
         [0023]    Further, when an extensive infrastructure of recharge-replacement stations is established along with the existing gasoline station network, the EV&#39;s driving range can be designed mainly according to its daily routine needs, say a 40-50 mile range. Such a shorter running range will reduce capacity requirement on the battery pack, and will lead to reductions in size and weight of the battery pack, and thus of the battery sub-packs of the present invention. In return, installation of battery sub-pack compartments on EVs and recharging compartments in recharging arrays will become easier and more practical, which will promote EV productions and sales. It can be expected that with a growing usage of EVs, demands on gasoline will drop. Therefore, a foreseeable benefit from combing battery replacement stations with existing gasoline stations is to provide the gasoline stations an opportunity to expand a gasoline-only function gradually to a dual gasoline-plus-battery function. Such a co-existence of gasoline station and EV battery recharge-replacement station will extend the lifespan of many gasoline stations. 
         [0024]    Further, with appropriate financial arrangements among relevant parties, including EV manufacturers/dealers, buyers, battery manufacturers, station owners/operators and financing institutions, electric vehicles can be sold with a deduction of battery cost, which will be paid off by EV owners when they pay recharge-replacement fees. In other words, instead of paying a significant total amount of money for the expensive rechargeable battery sub-packs, an EV buyer can divide the battery cost into insignificant fractions and pay it off over a long period of time of ownership of the EV. This arrangement will actually define the battery pack as a separate product from the purchased EV. With a continuous payment of the fractioned battery costs in recharge-replacement fees, an electric vehicle owner will no longer worry about battery life. 
         [0025]    Finally, the present invention will enhance collaborations among automobile manufacturers, rechargeable battery manufacturers, and gasoline producers that currently operate gasoline stations. In addition, the present invention, if implemented, will stimulate R &amp; D and manufacturing of instrumental devices for operational controls of the recharge-replacement system, such as the on-vehicle sub-pack control system and panels, and the recharging array control system and panels. 
         [0026]    It should be pointed out that the battery sub-pack case of the present invention can be manufactured as a stand-alone recharging unit so that it can be used in other settings, such as residential garages or small business parking shops. Owning a group of stand-alone recharging units at home or by small business owners in their convenient format will allow many EV drivers to manage their EVs in a more flexible way, if they prefer. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0027]      FIG. 1  is a perspective diagram of an EV battery recharge-replacement system of the present invention. 
           [0028]      FIG. 2  is a perspective diagram showing five locations of EV battery sub-pack compartments in a preferred embodiment of the present invention. 
           [0029]      FIG. 3  is a perspective diagram showing structural components and their relative relations of a battery sub-pack, its holding case and the compartment accommodating the holding case. 
           [0030]      FIG. 4  is a perspective diagram showing an EV battery sub-pack in its holding case in a sub-pack compartment under the driver&#39;s seat, and an on-vehicle sub-pack control panel. 
           [0031]      FIG. 5  is a perspective diagram showing a preferred location of the fifth battery sub-pack compartment in the rear trunk of an EV. 
           [0032]      FIG. 5   a  is a cross-section view of cross-section A-A as delineated in  FIG. 5 . 
           [0033]      FIG. 6  is a perspective view of a recharging array of the present invention. 
           [0034]      FIG. 7  is a perspective view of a multi-step supporting cart to support the holding cases and battery sub-packs of the recharging array of the present invention. 
           [0035]      FIG. 7   a  is a diagram showing details of Section B as delineated in  FIG. 7 . 
           [0036]      FIG. 8  is a perspective diagram showing how an EV battery sub-pack is dismembered into two to four sub-sub-packs (ss-packs) in the longitude direction (L-direction). 
           [0037]      FIG. 9  is a perspective diagram showing how the ss-packs are connected to form and function as a sub-pack in L-direction. 
           [0038]      FIG. 10  is a perspective diagram showing how an EV battery sub-pack is dismembered into two to four sub-sub-packs (ss-packs) in the latitude direction (W-direction). 
           [0039]      FIG. 11  is a diagram showing how two adjacent ss-packs are connected to form and function as a sub-pack in W-direction. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0040]    The description herein is presented progressively with  FIG. 1  through  FIG. 11 , in which the same numerals indicate the same components. 
         [0041]      FIG. 1  is a demonstration of a preferred embodiment of the present invention. In  FIG. 1 , an electric vehicle (EV)  1  is parked near a recharging array  2  in a recharge-replacement station. On said EV  1 , there are a few battery sub-pack compartments  3 . In said recharging array  2 , there are a few recharging compartments  4 . Each said sub-pack compartment  3  and said recharging compartment  4  has a sub-pack holding case  5  in it. Said holding case  5  is installed on a pair of sliding rulers  6 , so that said holding case  5  can be pushed into or pulled out from the said compartment  3  or said compartment  4 . The dimension of said holding case  5  is such that accommodates an EV battery sub-pack  7 . 
         [0042]    When said battery sub-pack  7  in said EV  1  is drained and needs to be replaced (this drained sub-pack is hereafter denoted as  7 - d,  where d represents “drained”), its holding case  5  is pulled out from said sub-pack compartment  3 . Said battery sub-pack  7 - d  is unlocked and removed. Said sup-pack  7 - d  can be placed on a carrying cart for transporting to said recharging array  2  (the carrying cart is not a part of the present invention and thus not shown in  FIG. 1 ). At said recharging array  2 , a recharging compartment  4  is opened, and its sub-pack holding case  5  with a fully-charged battery sub-pack  7  (hereafter denoted as  7 - c,  where c represents “charged”) is pulled out. Said sub-pack  7 - c  is unlocked and removed to the carrying cart. Said sub-pack  7 - d  is placed in the recharging holding case  5 , which is then reinstalled into said recharging compartment  4  for recharging. The said sub-pack  7 - c  is moved to said EV  1  and installed in the EV&#39;s holding case  5 . Said holding case  5  is then reinstalled into said sub-pack compartment  3  of said EV  1 . Other battery sub-packs on said EV  1  can be replaced with the same procedure. Said EV  1  is then ready for running on the newly installed sub-pack  7 - c.    
         [0043]      FIG. 2  shows the locations of five battery sub-pack compartments  3  on an EV  1  in a preferred embodiment of the present invention. The first four said compartments (labeled as  3   a,    3   b,    3   c,  and  3   d,  respectively) are under driver&#39;s seat, left rear seat, passenger&#39;s seat, and right rear seat, respectively. The fifth compartment  3   e  is in the rear trunk of said EV  1 . A sub-pack holding case  5  is installed in each of said first four compartments with a pair of sliding rulers  6  (shown in  FIG. 1 ). Said fifth compartment  3   e  does not have a pair of sliding rulers. Instead, a sub-pack holding case  5  is fixed in said compartment  3   e.  Also shown in  FIG. 2  is a battery sub-pack control panel  9 , which is used to exhibit capacity statuses of all battery sub-packs and to input driver&#39;s instructions for sub-pack operation. 
         [0044]      FIG. 3  shows the structural components of a sub-pack compartment  3  ( 3   a,    3   b,    3   c,  or  3   d,  but not  3   e,  in  FIG. 2 ) on an EV  1 , its holding case  5 , and a sub-pack  7  ready for installation. In  FIG. 3 , said compartment  3  has a door  15  that is hinged with two fixed hinges  16  (only portion of one hinge is seen in  FIG. 3 ) at the lower edge of the opening of said compartment  3 . Along the inside perimeter of said door  15  runs a sealing strip  17 , which is made of water-proof materials such as rubber. In addition, on the inner surface of said door  15  there are two pressing buttons  41  that can press on said sub-pack  7  inwardly when said door  15  is closed (in  FIG. 3  only on pressing button is shown). Said door  15  opens and closes vertically, and when closed, stays closed with a push-in latch pair  18 . Said door  15  swings vertically by  180  degrees on said hinges  16  for a full open and then hangs on said hinges  16 . Said sub-pack holding case  5  has an open top and an open rear, and is installed within said compartment  3  on two sliding-ruler pairs  6   a - 6   b  (only one pair is seen in  FIG. 4 ), whose two moving partners  6   a  are fixed on the outer surfaces of the holding case&#39;s left sidewall and right sidewall, respectively, and whose two unmoving partners  6   b  are fixed on the inner surfaces of said compartment&#39;s left sidewall and right sidewall, respectively. Said two sliding ruler pairs  6   a - 6   b  allow said case  5  to move into and out from said compartment  3  easily. At the rear edge of the solid bottom of said case  5 , a V-shape supporting leg  19  is attached with two hinges  20 , which allow said supporting leg  19  to swing vertically by 180 degrees. When in a downward position, one end of said supporting leg  19  touches the ground so that said supporting leg supports said case  5  when it is fully out from said compartment  3 . The solid front sidewall of said holding case  5  has two holes, through which an anode cable  21  and a cathode cable  22  come out. Said anode cable  21  has an anode clamp  23  at its end. Said cathode cable  22  has a cathode clamp  24  at its end. The other ends of said anode cable  21  and said cathode cable  22  (not shown in  FIG. 4 ) are to provide power to various functional units of said EV  1  when a battery sub-pack  7  is installed in said case  5 . 
         [0045]    Also shown in  FIG. 3  are a fastening belt  25  with a tab (i.e., a male buckle)  26  attached at one end, and another fastening belt  27  with one end going through a female buckle  28  with a release lever  29 . The other end of said belt  25  is fixed at the center top edge of a spacing block  31  at the front lower corner of said case  5 . The other end of said belt  27  is fixed at the center of the rear edge of the solid bottom of said holding case  5 . Said female buckle  28  allows said belts  25  and  27  to be tightened, by pulling the free end  27   a  of said belt  27 , after said tab  26  is inserted in said female buckle  28 . Said release lever  29  is used to release said tab  26 . At the center of the rear edge of the solid bottom of said case  5 , there is a rectangular notch  30  which allows said belt  27  to get through. 
         [0046]    In  FIG. 3  also, a battery sub-pack  7  is about to sit into said case  5 . Said spacing block  31  is to position said sub-pack  7  and to allow a space between said sub-pack  7  and the solid front sidewall of said case  5  for said anode cable  21  and its clamp  23 , and said cathode cable  22  and its clamp  24 . The distance between the out-facing surface of said spacing block  31  and the front edge of said notch  30  is slightly smaller than the length of said sub-pack  7 , so that said sub-pack  7  can tightly fastened when said belt  25  and said belt  27  are tightened. Each of the inside surface of the left sidewall and the inside surface of the right sidewall of said case  5  has a slanting slope  32  at its lower one-third portion. The distance between the foot-lines of two said slanting slopes  32  is equal to the width of said battery sub-pack  7 , so that when said sub-pack  7  sits in said case  5 , said sub-pack  7  will not move laterally. 
         [0047]      FIG. 4  is a demonstration that a battery sub-pack  7  is installed in a sub-pack compartment  3   a  under a driver&#39;s seat  40  of said EV  1 . Note that the demonstration in  FIG. 4  represents also sub-pack compartments  3   b,    3   c,  or  3   d,  but not  3   e,  of said EV  1 . For sub-pack compartment  3   e,  see demonstration in  FIG. 5 . Said sub-pack  7  and its holding case  5  are secured by a pair of tightened fastening belts  25  and  27 . As shown in  FIG. 4 , said fastening belt  27 , when tightened, goes through said rectangular notch  30 . In  FIG. 4 , said supporting leg  19  is in its upward position, and said compartment door  15  is in a fully open position, showing said sealing strip  17  and said two pressing buttons  41 . Also shown in  FIG. 4  is a battery sub-pack control panel  9  at a convenient location close to the dashboard of said EV  1 . Said sub-pack control panel  9  has a keypad  9   a,  a display screen  9   b,  a group of anode wires and a group of cathode wires (not seen in  FIG. 4 ), with one of anode wires and one of cathode wires being connected to anode cable and cathode cable, respectively, of each sub-pack holding case  5 . Said control panel  9  also contains a computerized program (not seen in  FIG. 4 ) to manage power delivery from individual sub-packs among said sub-pack compartments  3   a,    3   b,    3   c,    3   d,  and  3   e.    
         [0048]      FIG. 5  demonstrates a preferred location of the fifth sub-pack compartment  3   e  on said EV  1 . Said compartment  3   e  is located in a rear portion in the EV&#39;s rear trunk  33  and is easily accessible when the trunk cover  34  is lifted. Being different from other sub-pack compartments  3   a,    3   b,    3   c,  and  3   d,  said compartment  3   e  has a sub-pack holding case  5  fixed at its location. Said compartment  3   e  and said holding case  5  have all components as described in  FIG. 3 , except two pairs of sliding rulers. In addition, said compartment  3   e  has a flat top-cover  35 , instead of a compartment door. It should be noted that if a sixth battery sub-pack would be needed for more power and longer driving capability, another compartment could be easily installed side by side with said compartment  3   e.    
         [0049]      FIG. 5   a  is a cross-section view of cross-section A-A as indicated in  FIG. 5 , showing said slanting slope  32  of said holding case  5 . 
         [0050]      FIG. 6  demonstrates a recharging array  2 , with a battery sub-pack  7  being installed in a recharging compartment  4  while other four recharging compartments are closed. Said sub-pack  7  and its holding case  5  are secured by a pair of tightened fastening belts  25  and  27 . Said fastening belt  27 , when tightened, goes through said rectangular notch  30 . Also shown in  FIG. 6  is a battery recharging control panel  36  at the top portion of said recharging array  2 . Said recharging control panel  36  has a keypad  36   a,  a display screen  36   b,  a group of anode wires and a group of cathode wires (not shown in  FIG. 6 ), with one of anode wires and one of cathode wires being connected to anode cable and cathode cable, respectively, of each sub-pack holding case. Said recharging control panel  36  also has a computerized controller (not seen in  FIG. 6 ) to schedule and operate charging processes for individual sub-packs in said recharging array  2 . Said recharging compartment  4  has a compartment door  37 , which has a door lock  38  and a door knob  39 . Said door lock  38  can be controlled either by a manual key or keying in a special code from said keypad  36   a.  Said door  37  is made with strong and rust-resistant material to endure continuous longtime exposure to the atmosphere. Similarly, along the inside perimeter of said door  37  runs a sealing strip  17 , made of water-proof materials such as rubber. On the inner surface of said door  37 , there are two pressing button  41 , which will press said sub-pack inwardly when said door  37  is closed. 
         [0051]      FIG. 7  demonstrates a multi-step supporting cart  42  of the present invention. Said supporting cart  42  has four all-way wheels  43 , a handle  44 , and multiple supporting steps ( FIG. 7  shows a 5-step cart to match a 5-compartment recharging array as shown in  FIG. 6 ). Each supporting step will support a corresponding recharging case  5  and a sub-pack  7  at the same height.  FIG. 7   a  is a magnified form of Section B in  FIG. 7 , showing details of how said recharging case  5  is secured by a turning hook  45  and a hooking pin  47  on the corresponding supporting step. Said hook  45  is attached to the outer surface of the left sidewall of said recharging case  5  by a bolt  46 . Said hook  45  can turn clockwise on said bolt  46  to hook with said hooking pin  47  so that said supporting cart  42  will stay with said recharging case  5  during loading and/or unloading operation of said sub-pack  7 . 
         [0052]      FIG. 8  shows how said battery sub-pack  7  could be further divided into two, three or even four sub-sub-packs (ss-pack), denoted as  8   a,    8   b,    8   c,  and  8   e  in the longitudinal direction (i.e., L-dimension in  FIG. 8 ).  FIG. 9  demonstrates the structure of each ss-pack and how those ss-packs connect to each other. Each ss-pack has a lifting handle  10  on its top surface for griping and lifting. The first said ss-pack  8   a  has an anode clamp-able connector  11  and a cathode clamp-able connector  12 , which connect to an anode cable clamp  23  and a cathode cable clamp  24  (not shown in  FIG. 9 , but in  FIG. 3 ), respectively, of said holding case  5  for power delivery (on an EV) or for recharging (in a recharging array). On the front surfaces of the second ss-pack  8   b,  third ss-pack  8   c  and fourth ss-packs  8   d,  there are a male anode connecter  13  and a female cathode connecter  14  (they are seen on the front surface of said third ss-pack  8   c  only in  FIG. 9 ). On the rear surfaces of the first ss-pack  8   a,  second ss-pack  8   b  and third ss-pack  8   c,  there are a female cathode connector  14  and a male anode connector  13  (they are seen on the rear surface of said second ss-pack  8   b  only in  FIG. 9 ). All ss-packs will align precisely for correct and tight connections between their male connectors  13  and the female connectors  14  of their neighboring ss-packs after they are positioned and tightened in said case  5  by said fastening belts  25  and  27 . 
         [0053]      FIG. 10  shows how said battery sub-pack  7  could be further divided into two, three or even four sub-sub-packs (ss-pack), denoted as  8   a,    8   b,    8   c,  and  8   e  in the latitudinal direction (i.e., W-dimension in  FIG. 10 ).  FIG. 11  uses two latitudinal ss-packs to demonstrate the structure of each ss-pack and how those two adjacent ss-packs connect to each other. Each ss-pack has a lifting handle  10  on its top surface for griping and lifting. On their front end surfaces, the first said ss-pack  8   a  has an anode clamp-able connector  11 , and the second said ss-pack  8   b  has a cathode clamp-able connector  12 , which connect to an anode cable clamp  23  and a cathode cable clamp  24  (not shown in  FIG. 11 , but in  FIG. 3 ), respectively, of said holding case  5  for power delivery (on an EV) or for recharging (in a recharging array). On their rear surfaces, both said ss-pack  8   a  and ss-pack  8   b  have a male snap-connecter  48 . Two said male connecters are linked by a removable cable  49  which has one female connecter  50 . Said female snap-connecter can snap tightly with said male snap-connecter  48 , thus providing a secured connection between two adjacent ss-packs  8   a  and  8   b.