With timer

The output current of such a charger is cut off after a predetermined time. These chargers were most common for high capacity Ni-Cd batteries in the late 1990s.

(for low-capacity Ni-Cd consumer batteries, a simple charger is usually used).

It is common to find this type of charger for sale along with a battery pack. The charging time is configured for them. If other batteries of lower capacity are used in them, they may be overcharged. On the other hand, if batteries with a higher capacity than the original ones are charged, they will only be partially charged. Advances in this type of technology increase battery capacity every decade, so an older charger may only partially charge current batteries.

Timer-based chargers also have the disadvantage of causing overloads in batteries that, even if they are adequate, are not completely discharged when they are charged.

Intelligent

The output current depends on the battery status. This charger controls the battery voltage, its temperature and the time it has been charging, providing an adequate charging current at all times. The charging process ends when the appropriate relationship between voltage, temperature and/or charging time is obtained.

In Ni-Cd and NiMH batteries, the voltage that the battery can offer increases little by little during the charging process until the battery is fully charged. After this the voltage decreases, which indicates to a smart charger that the battery is fully charged.

A typical smart charger charges the battery to 85% of its maximum capacity in less than an hour, then switches to trickle charging, which requires several hours to achieve a full charge.

Generally, smart battery chargers have different charging modes, depending on the type of battery (Acid or Gel) and the state in which they are found: a good state requires a normal charge, while if the batteries have remained discharged for a long time they require equalization. Depending on the charging mode, the devices powered by the battery bank may or may not be left connected.[2]​.

Purpose

Its purpose is to obtain a fast charger that can use a control circuit of the battery itself to achieve a fast charge in this way without damaging the elements of its batteries. Many of these chargers have a fan to keep the temperature controlled. They usually act like a normal charger - charges in one night - if used with normal NiMH batteries, which do not have a control circuit. Some, such as those manufactured by Energizer, can quickly charge any NiMH battery even if it does not have the control circuit. At an industrial level

It is used to recharge the low battery of electronic devices such as: cell phones, radios, laptop batteries, etc.

Portable or external

It allows you to charge different electronic devices such as mobile phones and tablets "Tablet (computer)") among others. It is generally known as a Power Bank or external battery and consists of a portable device that can supply power from its built-in batteries through one, or several, USB ports.

They are usually also recharged by USB power.

By pulses

Some chargers use pulse charging technology in which a train of direct current pulses is applied to the battery, whose rise time, period, frequency and amplitude are controlled with great precision. This technology is often said to work with batteries of any size, voltage, capacity or chemical composition, including valve-regulated automotive batteries. Using pulse charging, high voltage spikes can be applied without overheating the battery. In a lead-acid battery, this breaks down the lead sulfate crystals, extending the life of the battery.

Several types of pulse chargers are patented while others are freely licensed.

Some chargers use pulses to check the battery status as soon as you connect the charger, then continue charging at constant current during the fast charging period and finally return to using pulse charging every so often to maintain the charge.

Inductive

Inductive chargers make use of electromagnetic induction to charge batteries. A charging station sends electromagnetic energy through inductive coupling to an electrical device, which stores this energy in batteries. Charging is achieved without physical contact between the charger and the battery. It is the most used charging system in electric toothbrushes; Because there is no electrical contact there is no danger of electrocution. Each inductance is referred to the generated magnetic field.

With timer

The output current of such a charger is cut off after a predetermined time. These chargers were most common for high capacity Ni-Cd batteries in the late 1990s.

(for low-capacity Ni-Cd consumer batteries, a simple charger is usually used).

It is common to find this type of charger for sale along with a battery pack. The charging time is configured for them. If other batteries of lower capacity are used in them, they may be overcharged. On the other hand, if batteries with a higher capacity than the original ones are charged, they will only be partially charged. Advances in this type of technology increase battery capacity every decade, so an older charger may only partially charge current batteries.

Timer-based chargers also have the disadvantage of causing overloads in batteries that, even if they are adequate, are not completely discharged when they are charged.

Intelligent

The output current depends on the battery status. This charger controls the battery voltage, its temperature and the time it has been charging, providing an adequate charging current at all times. The charging process ends when the appropriate relationship between voltage, temperature and/or charging time is obtained.

In Ni-Cd and NiMH batteries, the voltage that the battery can offer increases little by little during the charging process until the battery is fully charged. After this the voltage decreases, which indicates to a smart charger that the battery is fully charged.

A typical smart charger charges the battery to 85% of its maximum capacity in less than an hour, then switches to trickle charging, which requires several hours to achieve a full charge.

Generally, smart battery chargers have different charging modes, depending on the type of battery (Acid or Gel) and the state in which they are found: a good state requires a normal charge, while if the batteries have remained discharged for a long time they require equalization. Depending on the charging mode, the devices powered by the battery bank may or may not be left connected.[2]​.

Purpose

Its purpose is to obtain a fast charger that can use a control circuit of the battery itself to achieve a fast charge in this way without damaging the elements of its batteries. Many of these chargers have a fan to keep the temperature controlled. They usually act like a normal charger - charges in one night - if used with normal NiMH batteries, which do not have a control circuit. Some, such as those manufactured by Energizer, can quickly charge any NiMH battery even if it does not have the control circuit. At an industrial level

It is used to recharge the low battery of electronic devices such as: cell phones, radios, laptop batteries, etc.

Portable or external

It allows you to charge different electronic devices such as mobile phones and tablets "Tablet (computer)") among others. It is generally known as a Power Bank or external battery and consists of a portable device that can supply power from its built-in batteries through one, or several, USB ports.

They are usually also recharged by USB power.

By pulses

Some chargers use pulse charging technology in which a train of direct current pulses is applied to the battery, whose rise time, period, frequency and amplitude are controlled with great precision. This technology is often said to work with batteries of any size, voltage, capacity or chemical composition, including valve-regulated automotive batteries. Using pulse charging, high voltage spikes can be applied without overheating the battery. In a lead-acid battery, this breaks down the lead sulfate crystals, extending the life of the battery.

Several types of pulse chargers are patented while others are freely licensed.

Some chargers use pulses to check the battery status as soon as you connect the charger, then continue charging at constant current during the fast charging period and finally return to using pulse charging every so often to maintain the charge.

Inductive

Inductive chargers make use of electromagnetic induction to charge batteries. A charging station sends electromagnetic energy through inductive coupling to an electrical device, which stores this energy in batteries. Charging is achieved without physical contact between the charger and the battery. It is the most used charging system in electric toothbrushes; Because there is no electrical contact there is no danger of electrocution. Each inductance is referred to the generated magnetic field.