Motorists may carry jumper cables in case of accidental discharge of the vehicle battery (for example, by headlights or ignition switch left on while the engine is not running). Safe procedures for connecting and disconnecting cables are given in the vehicle manual.[1]
Jumper cables
(1) to (4) is a safe sequence to connect jumper cables from the dead battery on the left to the good battery on the right. If (2) were connected before (1) and the loose end accidentally touches bare metal on its car, the good battery is shorted; shorting the dead battery is less risky. (4) is connected to bare metal away from the battery to keep any sparking on circuit completion away from hydrogen potentially released by the battery. Cables are disconnected in reverse order.For other uses, see Jumper cable (disambiguation).Jumper cable connected to positive postJumper cables, also known as booster cables or jump leads, are a pair of insulated wires of sufficient capacity with alligator clips at each end to interconnect the disabled equipment/vehicle with an auxiliary source, such as another vehicle or equipment with the same system voltage or to another battery. The alligator clips may be covered in insulation to prevent inadvertent shorting. Clips may be made of copper or steel. Alligator clips are generally marked by black (−) and red (+) to indicate the polarity.[2]
Motorists and service garages often have portable battery chargers operated from AC power. Very small "trickle" chargers are intended only to maintain a charge on a parked or stored vehicle, but larger chargers can put enough charge into a battery to allow a start within a few minutes. Battery chargers may be strictly manual, or may include controls for time and charging voltage. Battery chargers that apply high voltage (for example, more than 14.4 volts on a 12 volt nominal system) will result in emission of hydrogen gas from the battery, which may damage it or create an explosion risk. A battery may be recharged without removal from the vehicle, although in a typical roadside situation no convenient source of power may be nearby.
Battery booster and jump starter[edit]
AC charger with boost feature battery chargers have a boost, engine start, or engine assist feature. Despite being able to assist in jump starting a dead vehicle battery, these types of battery chargers perform their task over a longer period of time, rather than an instantaneous boost. Boosting a dead battery through a battery charger can take anywhere from five to twenty minutes depending on the depth-of-discharge (DOD), health of the vehicle battery, and type of engine (engine displacement). AC power is not usually available for a roadside boost.
Jump starters are portable battery devices that allow for jump starting of vehicles. These devices operate similar to jumper cables but do not require an additional vehicle to provide the power needed to boost the dead vehicle battery. Jump starters come in various sizes (typically rated in Amps). Most jump starters on the market today use lead-acid batteries and claim 300−1700 amp ratings. The main disadvantage of lead-acid jump starters is weight, size and battery chemistry. Lead-acid jump starters can be extremely heavy and large, making them less than convenient when transporting between vehicles. Lead-acid batteries may self-discharge if they develop a condition called sulfating, which permanently decreases battery capacity. It is entirely possible to destroy a new lead-acid battery within months, requiring a replacement.
Jump starters using lithium-ion batteries began appearing i on the market in 2013. Most lithium jump starter brands use a high discharge lithium polymer or lithium-ion battery. Lithium jump starters are extremely compact and lightweight, as much as 90% smaller than lead-acid equivalents.[citation needed]
Push starting[edit]
Main article: Push startA vehicle with a manual transmission may be push started. This requires caution while pushing the vehicle and may require the assistance of several persons or another vehicle. If the vehicle battery cannot provide power to the ignition system, push starting may be ineffective. Most vehicles with automatic transmissions cannot be started this way because the hydraulic torque converter in the transmission will not allow the engine to be driven by the wheels.
Car Battery Booster Cable -2000 AMPS,