How Does a Float Charger Work?

Float charging is a way of charging a battery which keeps it continually powered at full capacity. As such, this method of charging is often used for emergency power supplies to keep a battery from losing its charge while it sits idle. In the airline industry, this can be important for maintaining a reliable back-up power supply in case of electrical failure or for keeping batteries stored for future installation. Float charging is also commonly used as a backup for telecommunication equipment which may need to be used in an emergency. Float charging is a valuable process and having a basic understanding of it can help you use the method effectively while avoiding possible issues.

Batteries are devices which convert electrical energy into chemical energy to be stored for a period of time and then be returned to electrical energy again, when needed. As a battery charges, the amount of electrical current or voltage rises until its peak limit is reached. “Float” is the name given to the final stage of the charging process, when a battery is at the highest capacity it can possibly be. In order to keep a battery at full capacity, batteries can be hooked up to a float charger which transfers a trickle of uninterrupted power supply to the battery high enough to keep it at full power but not so much that it harms the battery. Since the voltage of an electrical current is affected by temperature, some float chargers have a built-in temperature compensation circuit to adjust to temperature changes.

Float charging is often coupled with boost charging, which can quickly recharge a battery after it has been depleted in an emergency use. The booster part of a float charger has an output up to 2.70 V per cell for recharging the battery for a flooded type and up to 2.4 to 2.45 for VRLA batteries. The trickle charging part has an output just enough to compensate for constant self-discharge and has a voltage level of 2.25 V per cell. The amount of voltage output necessary can vary by the size of the battery with these values being the standard output capability.

Float charging is a technique regularly used in the airline industry. Telecommunication equipment, airplane engine tools, and other electrical components can benefit from having a fully charged battery on standby in case of an emergency. Batteries may also be put into float charging to keep them at full capacity while sitting idle before transport or installation. If you are on the look-out for high-grade batteries, chargers, and other aviation parts, Aviation Parts Circuit is here to assist you! On Aviation Parts Circuit, owned and operated by ASAP Semiconductor, customers can find the aircraft parts and components they need, all with aircraft-grade accreditation. Browse our online catalog of aircraft components or send an Instant Request for Quote (RFQ) form today to receive a custom competitive quote in 15 minutes or less!


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