Use a special charger, such as an RV or boat charger, that has multiple outputs (best). Connect the two batteries in series, and use a 24V charger (ok, if the two batts are exactly the same). Connect the two batteries in parallel and use a standard 12V charger ( worst choice, one battery tends to hog the current, and they receive unequal charges). See the links for a dual-output charger I Googled.
If they are wired in parallel they are both charged at the same time. Basically the two batteries act like one larger battery.
Yes if they are connected in parallel but I would not recommend it. Just charge them one at a time.
With the batteries in series, the alternator provides the same current, and therefore the same charge to all the batteries. The alternator can take no account of any current being drawn from the 12V take off point. Part of the charge current is being fed to the 12V load and not to the batteries. Therefore, the 12-24V batteries are being fully charged while the 0-12V batteries are being partially charged. Over a period of time, the difference between the charge levels will become more obvious.
They were both free of charge.
The two batteries can be wired in series BUT unless they are identical batteries in an identical state of charge they should be checked regularly to see if one of them is fully charged (the voltage has risen to 14.5 volts).
They were both free of charge.
No you cannot.
You need to multiply the number of coulombs by the number of volts. If the two batteries are in series, then you can add the voltage of both batteries.
It depends how they are connected. If the terminals of two 12 volt batteries batteries are connected to the same circuit (in parallel) then there is no change in the flow of current- it will just last for twice as long a time. But if two opposing terminals of the batteries are connected to each other first and the free terminals then connected to the circuit (in series) then there would be a total voltage of 24 volts and twice as much current would flow. The two batteries would last for the same length of time as one battery on its own.
24 Volts.
step up trasnsformer <<>> As suggested above transformers do not work on DC installations. You will need to use two 12 VDC batteries in series with each other to obtain the 24 VDC needed to operate the motor. Connect a jumper between the two batteries with a wire the same size as the wire coming from the motor. The jumper will go from the negative of one battery to the positive of the second battery. The two remaining posts will connect to the motor and have a potential of 24 VDC.
With the cost of new batteries being as high as they are today, buying rechargeable and replacement battery sets is much more cost-effective. This choice also reduces the amount of hazardous waste emptied into the landfills. Recharging devices and battery sets can be purchased for about the cost of 50 batteries. Most have a recharge number of at least 1,000. When used incorrectly, these batteries may have a much shorter life. This article will explain how to maximize the life of rechargeable batteries.Be sure to use the batteries and chargers from the same manufacturer. For example, don't use a Duracell battery on an Energizer charger. Not all rechargeable batteries are made exactly the same, so this is very important. Some chargers may not be designed to charge other types of batteries, resulting in a slight charge and shorter overall life. Never over-charge a battery. When they are over-charged, they also overheat, which takes a great portion of the battery's life.Always use the entire charge on a battery. Every time the battery is placed in the charging unit, this initiates a new cycle. Most people are unaware of this fact; it is not usually printed in instruction manuals or on the device's package. Using the battery for a while, then placing it on the charger when it has 30% of its charge cycle left will result in loss of that 30%. Each trip to the charger is what weakens the battery, even though it will be fully recharged. Always keep this in mind when deciding when to place batteries in the charger. Always keep a replacement set fully charged and ready to go, so it will be possible to use the entire charge cycle without being inconvenienced.Don't let charged batteries sit unused for long periods of time. It is best to use batteries as soon as they're charged - or shortly after. If the replacement batteries must sit for a long time, charge them no more than a week or two before they will actually be needed. However, don't let the battery sit with absolutely no charge. There should be a charge of about 20%-50% as it sits. When batteries sit unattended, they will automatically lose their charge. A completely empty battery will stop working faster and the number of effective charge cycles will be reduced if it sits empty for a long period of time. Batteries should be stored away from sunlight in a cool and dry location.