NOVELTY - The battery charger has multiple groove bars (35) formed in a bore of an outer cylinder (11). A slope seal seat (26) is connected with a right side of a scraper seal groove (24) that is formed in an inner diameter side of an inner cylinder (10). Multiple projection bars (34) are fixed in a circumference parallel portion (33). A spring (45) is connected with multiple micro columnar grooves (27, 27') along axial direction. A rear handle (46) is connected with multiple arm cylinders (44, 44') that are fixed in a front handle (43).    USE - Plane sliding-type liquefied petroleum gas (LPG) battery charger.    ADVANTAGE - The battery charger reduces sliding frictional power between the outer cylinder and the inner cylinder due to gun type structure with acoustic energy of the spring. The battery charger has better stability. The battery charger ensures smooth operation. The battery charger can rapidly manage gas leakage accident for manipulating switching operation of a ball valve. The battery charger ensures safety. The battery charger utilizes a Teflon (RTM: PTFE) seal seat that is provided with a columnar groove and a micro columnar groove so as to enhance adhesive strength due to pressure increase in contact surface. The battery charger ensures leak safety and low-friction function according to rotary motion of a filter. The battery charger reduces rotary motion frictional force through a penetration ball to secure lubrication effect. The battery charger reduces generation of fire or gas explosion due to spark generation when a plastic uninterruptible material collides with an external object so as to drop down gas leakage. The battery charger sets a scraper seal in an inner side of the inner cylinder. The battery charger is light in weight and simple in design. The battery charger is protruded to an outer side surface of a ball valve body by increasing internal pressure rapidly. The battery charger reduces mixing of contaminant with LPG while screwing a transparent cap nut. The battery charger prevents environment from being polluted by using a LPG filter. The battery charger can prevent consumption of extra-high voltage for spraying injector of the LPG.    DESCRIPTION OF DRAWING(S) - The drawing shows an exploded perspective view of a plane sliding-type LPG battery charger.    Inner cylinder (10)    Outer cylinder (11)    Scraper seal groove (24)    Slope seal seat (26)    Micro columnar grooves (27, 27')    Circumference parallel portion (33)    Projection bars (34)    Groove bars (35)    Front handle (43)    Arm cylinders (44, 44')    Spring (45)    Rear handle (46)