28

This is going to get a bit technical but should still be understandable even if you slept through chemistry classes. When is hydrogen dangerous? Just as with the fuel-air mixture in an engine, hydrogen is combustible only when it's within a range of concentrations. We use what are called the Lower Explosive Limit (LEL) and the Upper Explosive Limit (UEL) ...


21

It's because of a couple things: The battery is very dead and the alternator cannot put out enough power at idle RPMs to run the whole system and charge a battery. This leads to a lack of power which may kill one or more systems most likely the spark "ignition" system since this takes the most power and is necessary to run the car. In Fact you can remove ...


18

To answer your question, it will not cause any issues as long as the cables are connected correctly. If both donor cars are connected in parallel (negative to negative/positive to positive) to the recipient vehicle, there should be no issue.


17

With the description you give, I'd say you connected them backwards with about a 99%+ assurance. Large amounts of sparks followed by heat are both VERY BAD SIGNS (as you soon figured out) and almost always mean you have the jumpers on backwards. Never trust what the covers on the battery says. Check what the battery says to be sure. If there is no way to see ...


17

When you jump start a car, you are always putting the cars in a parallel circuit. Here's an illustration of parallel vs. series: Source Think of the bigger car's battery as the one on the left and the smaller car's battery as the one on the right. When you connect jumper cables, you connect the positive terminal on the bigger car to the positive terminal ...


15

The biggest thing to look at for me is the gauge of the wire. The reason I bring this up is, the higher the gauge (numerically) the thinner the wire. Thinner wire will require your jump-start procedure to take more time, as it takes a while to charge the battery before you'll have enough juice to get it running. Thinner wire cannot pass enough amperage to ...


14

I don't know the actual justification, but to me it makes sense to always attach positive first because it is easy to accidentally touch the lead to something else while installing. If the negative lead were already attached, then touching the positive lead to just about anything on the car that is metal would short out the battery.


13

There are two power systems on all electric cars (fully electric and hybrids alike). This is in conjunction with the much higher voltage battery packs which normally power the electric motors. The reason for this extra power system is to power things like lights, electronics, and HVAC systems (to name a few). Most hybrid vehicles (and never a fully electric ...


12

Your car thinks it is being stolen - jump starting a car looks a lot like hot-wiring a car to the computer. You need to do something that tells your car "it's OK, I own you". You can do this right after hooking up the cables, but before starting the engine, to minimize the annoyance to your neighbors. If you have a remote door key, lock and unlock the doors ...


12

No, you cannot. Well, you might be able to, but not in a feasible way in any likely manner. Electric Vehicles commonly have two separate electric circuits. One running at the normal 12V, which ties to all the common electronics that all other types of cars have. Light bulbs, radios, in many cases also a starter motor for the gasoline engine if it in fact ...


12

Anderson supplies a whole range of connectors with varying current ratings. Also, current ratings tend to be conservative: these are steady-state ratings. So a 50-amp connector can handle 50 A all day without overheating. That connector can handle more power for a short while. Similarly, jump leads are often far thinner than you'd expect because they only ...


11

You can get transient spikes from the other car while it's trying to start. Any battery or alternator issues that affect power quality will be transmitted to your car. The good news is that large 12v batteries make excellent buffers against power issues that might otherwise cause damage. However, it is still possible to suffer damage to your car from ...


11

The starter circuit should only draw whatever current it needs so the excess shouldn't cause any problem.


11

The two biggest disadvantage of lead acid batteries compared to the newer types like Li Ion are that they are heavier, and that they contain liquid acid. Another possible issue is that they can produce hydrogen gas. On the other hand, they are very inexpensive, have a long life expectancy, have a very high tolerance for overcharging without being damaged, ...


11

I am no expert in this topic, but I don't think a "cloud of gas" forms around the battery. Hydrogen gas is the lightest gas of them all (0.089 g/l) and won't pool up if leaked. It will simply rise as long as the bonnet is open because it is less dense than air, which is mostly much heavier nitrogen (1.25 g/l) and oxygen (1.4285 g/l). My guess is that the ...


10

Sounds to me like your starter motor is on the way out, as you are getting enough power, as a bump start is working, and sometimes you are able to start normally. This isn't that uncommon - they do take a lot of stress and load, and the internal friction can end up being too high for them to cope with. A temporary fix I have used in the past is to whack ...


10

Those numbers are the max that they can supply. Your starter will "automatically" use as much as it needs up to the max. If the starter needs more than those units can supply, the jumper will only provide its max. If your battery is only partly dead, i.e. it won't start, but the interior lights come on, you can use a smaller jumper than if your battery ...


10

There are no special safety issues related to snow and ice. In general, voltages up to 48V are considered safe for the human body. You can touch both contacts of a 12V battery, even with wet fingers. (Did you never touch the terminals of a 9V battery with your tongue? This hurts a little, but that's all) A 12V car battery can deliver several 100 Ampere, ...


9

Conventional lead acid batteries produce hydrogen gas as a byproduct of the charging process. This gas tends to collect in and around the battery. As you are aware making the final connection can generate a substantial spark. By making the frame connection the point where the spark occurs it is far enough from the hydrogen gas to avoid an explosion.


9

It sounds like you need a trickle charger or battery maintainer - this is a small charger than monitors the charge on the battery, and keeps it charged. Most modern cars have electronics that have a continuous drain on the battery - a trickle charger produces enough power to compensate for this drain, so that even if the car isn't driven for a few weeks the ...


9

The amp count tells you the maximum amount of current that the equipment can supply. Eg. Your car needs 600 amps to start: The 1000 amp jumper can handle it. Your car needs 1200 amps: The 1000 amp jumper can't do it. You'll have to find a bigger one. Be aware that this does not apply to voltage. If you have a 6V battery and you connect it to a 12V ...


9

Since you have a battery which isn't that old (most batteries have about a five year life span), I'd suggest you put it on a charger and try to recharge it. This will allow the battery to come back to full charge without putting an undue stress on your alternator. You have to decide if the time spent in recharging the battery is worth your time. To me, ...


9

Lead sulfate crystals form on the battery plates as the battery discharges. As the battery becomes more discharged the crystals go from being soft and fluffy to much harder. Recharged in time, the lead sulfate is converted back into sulfuric acid and lead. A month is entirely too long for a battery to remain discharged. Reversing a serious sulfation ...


8

Your description of connecting the two cars is correct. I want to emphasize making the last connection to the "bolt head" you mention. Any large piece of unpainted metal will do. The reason for this is to keep the resulting spark away from the battery. If they battery has been venting fumes, the spark can (although it's very unlikely) cause them to ...


7

The other answers failed to emphasize an important point: the 12V battery on hybrid cars is not designed to start an engine, being much smaller than typical automotive starter batteries. Thus, it may not have the cranking amps capacity to successfully start the other car. The 12V battery is merely there to provide power for lights and to boot up the computer ...


7

There's a joke in electronic engineering about transistors being invented to protect fuses. Basically, it means that transistors blow faster, and so a fuse is practically worthless for that purpose. It still protects the wiring from catching fire, but not the circuit from functional damage. To protect the circuit from functional damage, the designers ...


7

Yes, Lithium Ion batteries are capable of delivering the power required to turn over an engine. The thing I am most experienced with is the kind of batteries you put in remote controlled devices, so I will use those for reference. For all intents and purposes they are basically a consumer-friendly version of the bare cells you will find in the devices you ...


6

The cranking amps required to start an engine are not the same as the cranking amp rating of a battery. I don't know the amps required to start your car's engine, but if it is less than 400 amps, then it will work. Higher cranking amps in a battery yields additional benefits. The battery can be used for more starts because less capacity is used on each ...


6

Any ground (earth) location will work. On my '06 Silverado, there are places to hook the jumpers which are away from the battery. You don't even hook the jumpers to the battery no matter which way you're going (whether jumping or being jumped). As long as you have a good ground location, you're golden. Given two vehicles with alternative connection points (...


6

I can't think of any reason why you would damage the electronics in your car, unless you touched one of your jump leads somewhere you shouldn't and short something delicate or you connect the leads back to front. Connecting them back to front shouldn't damage electronics, as your car should have protection against this sort of thing, but it is the key thing ...


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