Cheep batteries are designed as general purpose not practical for high power drain demands. Expensive ones are specifically designed around high power drain equipment laptops right though to electric invalid, car to big rigs batteries. Includes battery packs for mobile scooters, electric bicycles, and fork lifts ect

The there are the common touch cell ( battery if you like ) and Lenten batteries for remote controls, calculators toys, gadgets and electronic hobby construction projects plus mobile phones . The common torch battery  range from the tiny cheep throw away triple A, double A and the large A. Then there is the expensive and Re-chargeable.

All batteries show electric power is made up of positive and negative voltages. One end is marked with a plus sign for positive and generally the other end not marked or a take away sign ( -) for the negative terminal.

The definition of voltage, it doesn't flow, only alive at each terminal. You can feel this with a pair 1.5V torch and pen light batteries. It doesn't matter what terminals. Bring together end to end a couple millimeter gap and sweep a millimeter side to side.

You will feel the live voltage at each end. If the same terminals you experience a repulsive force pushing each other away. If unlike terminals, you'll experience a similar force pulling each other together.

The positive terminal is a store of a lack of the negative particle of the atom called electrons making the terminal some what domineeringly positive. ( + ). The negative thermal ( - ) has the same  number of excess electrons making that terminal somewhat domineering negative

Touch cells ( or batteries if you like ) arranged connected in series add to a total voltage, while connected in parallel the total number of cells is always the same voltage as a single cell. The positive thermals are connected together. So too, the negative terminals connected together. There is an open positive and negative thermals.

Every electronic circuit and device is in always in parallel ( across ) all battery sources drawing the current flow of electrons repelled by the negative voltage though the circuit attracted by positive voltage in a steady direct stream known as the electron current flow expressed as a direct current.

The unit of this electron current is called amperage. All devices and circuits draw any current from a micro amp ( micro from the standard metric system for a millionth ) to a couple of amps.

All battery sources have a limited current supply. The tiny triple A pen light batteries a maximum of under a milliamp ( mill lee from the standard metric system for a thousandth. 075mA or 750 micro amps ). The same voltage of the large A size re-chargeables up to a couple of amps. If over drawn the voltage immediately drops loosing power. This maximum current is the threshold power output of the battery before the voltage drops under the load drawing current from the battery.

The output power of a device depends on the combination of the voltage of the device and required current drain. The device voltage it's current ratting of the load is known as it's power drain demand of the device on the battery called Wattage. The voltage and Wattage of devices is commonly given. Mathematics projects the current drain drawn from the device.

From Watts law the loads specified Wattage divide it's voltage projects it's current drain drawn the battery. I equals W over E law.

Algebra teaches us the law of mathematics tells us proof of this when we dived the devices wattage by the projected current drain gives us the deices voltage. E equals W over I law. We can muiltiply the projected current drain by the deices voltage that gives the wattage. W equals E I law. We can also muiltiply the devices voltage by the projected current drain that gives us the devices wattage W equals I E law.

An example of a electric bicycle battery typically 48V drawing a current of 17A, by watts W equals E I law gives us a 816W electric motor. This is a maximum power drain from the battery. If 17A is used up in by hour of travel time the voltage drops loosing power needing to be recharged. If 1A used in every hour lasts a total of 17 hours of travel time before needing to be recharged known as a 17 amp hour battery pack. Using up 17A in an hour of traveling time in one hour or 1A every hour lasting a total of 17 hours before needing to be recharged.

Electric inlaid scoter and wheelchair batteries are as much as 500A known as a 500 amp hour battery pack. The same laws apply using up 500A in an hour or 1A every hour before needing recharge.

The current supply of a battery arrangement is crucial in running a device or circuit. Only the voltage specified for cheep torch cells ( batteries if you like ) only designed for low power drain demands. Expensive ones particularly re-chargeable give not only voltage but the amp hour ratting, possibly even the wattage power.

By the standard metric system there is a thousand milliamps ( mA ) in1A. If a device or circuit draws only a milliamp from an expensive A size 1.5 one amp hour ratting touch battery if you like will last the equivalent of a thousand hours. A current drain of up to 1A would only last an hour. In other words 1A is a 1,000mA supply. Long lasting power is a high amp hour supply. The same law applies to lantern, motor vehicle, invalid scooter, wheelchair to electric bicycle batteries.

These are all specified in the voltage and the number of amps they can supply in an hour, possibly even specifying wattage. The amp hour ratting is the maximum current drain before the voltage drops loosing power from the electric motor in one hour.

If the current drain of a toy motor is higher than the current supply of the battery connected to it  can supply there is an immediate drop in voltage loosing output power from the motor straight way.

10mA is a dead short to new cheep triple A pen light touch battery. Current drain demand from any load at the maximum current supply only lasts a total of an hour or lasts longer drawing a smaller current. The current drain from every TV remote control button we press is about a milliamp at a time. The use we get from cheep triple A size batteries will only last total of hour at it's maximum current supply.

Brand new will have ample power for very short period of time before a decoration of the device gets worse and worse. The more used the more the current drain drops the voltage loosing the devise output power to send to the TV sensor.

TV and videos remote controls are notorious at this kind of problem using cheep batteries. Expensive throw away, last a lot longer because of a higher current supply. Better still with a re-chartable source always on standby using re-chartable high current drain supply or longer lasting at high current supply. Not only last long, but never need to replace the battery again.

This is why cheep batteries don't last long. More expensive types with a high current supply capability will last longer.

The tiny cheep throw away triple A is a maximum of 1 milliamp amp hour ratting. The standard metric system tells us there is a thousand micro amps in a milliamp. A current drain demand of a 10ma and more amp is a dead short from new to these little batteries.

There is a split second current drain demand of about a half a milliamp ( 500 micro amps half milliamp ) with TV audio, and video remote controls. Toys about a 750mA ( three quarter amp and more ).

A typical remote control for TV and other devices may require up to a 500mh ( half amp ) battery pack to last. A current drain of 1mA every time a button is depressed the control will last the equivalent of a 500 hours.

A typical cell phone may require up to a 100Ah or more battery pack to last. It will last the equivalent of a 100 hours if the maximum of your phone draws a milliamp at a total of an hour at  time. The long lasting staying power depends on a low current drain demand of the phone fitted with a high amp hour ratting battery pack.

There are a million micro amps in 1A. Imagine an extreme, a phone that only draws a maximum current drain demand of a micro amp fitted with a 2AH battery pack. Mathematics projects a equivalent total of 2 million hours before needing to be recharged. The battery will no doubt be worth more that the most expensive smart phone.

The same laws apply to all other devices such as a electric fork lift, mobile scooters, and electric bike motors drawing power from their battery's limited current supply. Some of these batteries are capable of supplying up 500 amps in an hour.

The law requires invalid electric scooters a maximum speed limit of a fast walking pace. Electric bicycles no more than equal lent  to normal bicycle cursing speed or they are classed as proper motor bike. Choosing a low current drain motor with a high amp hour ratting the battery last longer traveling times.

However, powerful forklift, invalid scooter, batteries are designed for frequent recharging called deep recycling to accommodate owners user habits. The habit an owner of a invalid scooter with a battery pack of 500Ah ratting demand may require every night charging ready for the next day for a year or so before needing to be replaced.

This also includes the habitual use of laptops away from mains power. Some of their batteries are as much as 6Ah ratings. At a current drain of 1A will last a total of 6 hours. They are also deep cycle battery's that can be recharged every day ready for the next day up to 18 months at a time.

Imagine the extreme with a 12Ah laptop battery at a maximum current drain demand of 1A from the laptop. Mathematics projects a battery like this with this kind of current drain demand will last up to a total of 12 hours before needing recharged.

Laptop and other computer device batteries don't like being toped up all the time. It shortens there recycling life. They like to be flattened flat they can't can't run any more before recharging. In contrast vehicles have engines continually running alternates all the time. Their batteries are constantly trickle charged. That's why car batteries are not deep cycle batteries.

Invalid scooters, electric wheel chair and electric bicycles haven't got that luxury so are deep cycle types.