Before going into the details, let us first know what is a battery tender. It is a charging device that plugs into a standard AC outlet and ‘intelligently‘ charges your vehicle’s battery. It transfers power in the form of amps to a 12v battery while maintaining a safe level of charge.
Over time a battery will slowly lose its internal charge and so they are essential if you have vehicles that are left inactive for long periods, particularly during winter months when low temperatures result in a more dramatic discharge.
The biggest clue however is in the name; it will ‘tend’ to your battery while you’re away, giving it the electrical TLC it needs to stay fresh, operational and fully efficient.
What makes a battery tender ‘intelligent’
It has internal sensors and intelligent microprocessor controlled circuitry, which enables it to constantly check and adapt to your battery’s level of charge.
Unlike trickle chargers, which have a reputation for ‘frying’ batteries, it can perform a series of functions based on the level of charge which ensure that there is no damage caused to your battery.
Whereas trickle chargers are known to over-charge and cause battery ‘boil out’, the sensors in a tender will actively monitor the condition and charge level of your battery using a series of modes to best suit the situation.
What is a battery tender mode
A ‘mode’ simply refers toa pre-defined bunch of settings that suit the current situation. There are four common modes that a battery tender uses:
Upon connecting it, it will conduct a series of checks to ensure the battery is functioning normally and detect the current level of charge.
Bulk Charge Mode
If the battery is below a certain level of charge, it will activate bulk charge mode, delivering its full charge at a constant rate.
Once a certain level is reached, the battery tender will activate absorption mode, dropping the amps to a lower level for a predetermined period of time or until the optimum voltage level has been reached.
Once the battery has reached an optimum charge level the tender will switch into what is commonly known as ‘float’ mode, continuously monitoring and maintaining the voltage at full charge for as long as it is connected.
Why you should use a battery tender
The benefits of using it are plentiful and go far beyond simply taking care of your battery.
From minimal power usage (comparable to the power consumption of a light bulb), visual charging indicators and a compact, lightweight construction, there are countless reasons why these are the ideal choice when it comes to charging.
Most importantly, being able to ‘set it and forget it’ unlike trickle chargers means you can leave your battery connected to the tender for weeks, months or even years, safe in the knowledge that your vehicle’s power source is being looked after and will serve you well for years to come.
The above are some very important points that answer what is a battery tender.