Will A Trickle Charger Charge A Dead Battery?

How can you use a trickle charger to charge a dead car battery?

Batteries could die for so many reasons; storing your car for a long period of time without starting it, parking it outdoors under a freezing condition, leaving a trunk door open or the headlights on after turning off the engine, and more.

All batteries self-discharge, that’s why when you store your car for months, your battery might not have enough power to start it when you finally want to bring it out of storage. This is why you need a trickle charger, a device that, when attached to a battery, slowly charges it to keep it from dying even in storage for a time. But, will a trickle charger charge a dead battery? We will find the answer to that question later in this article.


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But What Exactly Is A Trickle Charger?

A trickle charger is an electrical battery charger that charges batteries at a rather slow yet steady rate. It is distinguished from the usual car battery charger for its low amperage, or it is only capable of delivering a low charging ampere. Although there is no definitive rule on how much power a trickle charger delivers, the average delivery is from 1 to around 3 amps. As a battery self-discharges, a trickle charger replaces the lost energy gradually, thus, preventing the battery from being depleted.

There are even some trickle chargers that are meant to be connected to the battery for a protracted time without the risk of explosion or the battery being damaged. This type of a trickle charger is ideal for cars that are garaged during the winter months or for vehicles that are not used regularly but needed during an emergency situation to ensure that there is power when it is needed. A trickle charger prevents the battery from being totally discharged or depleted from lack of use.

How Does A Trickle Charger Work?

Trickle battery chargers work like an ordinary charger…they deliver electric current to car batteries to supply it with power. The difference between a trickle charger from the ordinary car battery charger is that it delivers an electric current at a gentler and lower rate to avoid the risk of overcharging. Ordinary car batteries, on the other hand, delivers a constant voltage, notwithstanding the energy level of the battery. When not attended to, this could lead to either a undercharge or overcharge.

Battery maintainers as what trickle chargers are sometimes called, supply power to a battery at the same rate as a battery self-discharge. The name of this device describes exactly how it delivers the electricity, …in trickles. Although power is delivered in trickles, there is also a risk of overcharging, thus the need for monitoring, unless you are using the automatic type with an automatic on and off feature or a float mode.

Trickle chargers have a battery regulator to determine the charging rate to avoid overcharging. The battery should be charged at the rate comparable to the battery self-discharge rate to ensure full battery capacity.

Fast Vs. Slow Charging

Getting to know the differences.Jump charging your dead battery could get your car running, but such a drastic method could shorten the useful life of your battery. The low yet steady charge provided by a trickle charger is a more reliable and exhaustive charge that results in extended battery life.

The science involved in the technology of lead-acid batteries is the reason why faster is not necessarily better. Electrical energy in lead-acid batteries is stored in an array of lead plates and an electrolyte solution composed of water and sulphuric acid. When the battery is discharged, the lead plates are chemically transformed into lead sulfate whereas the electrolyte becomes a very diluted compound of sulphuric acid and water.

When a battery charger is connected to a battery, electrical current flows into the battery which reverses the chemical process. The lead sulfate is transformed back into lead plates which in turn delivers the sulfate into the electrolyte to make it a more concentrated sulphuric acid and water solution again.

Of course, using a battery charger with a higher amperage will speed up the process and charge the battery faster, but it does have a disadvantage. Delivering power at a higher and faster amperage usually discharges a lot of heat that could cause off-gassing or even a battery explosion in extreme cases. It will also shorten the life of a battery.

This is where a trickle charger comes in. The slow yet steady delivery of power from a trickle charger will prevent off-gassing and the risk of an explosion and will give your battery longer useful life.

The Difference Between A Trickle Charger And A Battery Tender

First, let’s see what a battery tender is. It is a device, usually a 1.25 amp battery charger, that delivers power to a car battery keeping it in an operational level even if left inactive for a long period of time. It is a great device for vehicles that are left sitting in the garage for months without being used. It has the ability to charge a battery fully.

It has a system that monitors the level of charge in the battery. When the voltage has reached a preset level, it stops charging, thereby avoiding damage due to overcharging. When the sensors of the system perceive a drop in the voltage, that is when it resumes charging. This is one reason why a battery tender can be connected without a time limit.

On the other hand, a trickle battery charger needs to be connected and disconnected every now and then since it continuously delivers a charge. But such is the case for the older type of trickle charger. Presently there is a “smart trickle charger” that works exactly like a battery tender.

This smart trickle charger has an automatic on and off mechanism, or a float mode that turns on the trickle charger when the battery is dead or has a low voltage and continues to charge slowly until the battery is fully charged then turns the device off. It will resume charging again once the voltage drops. The “smart trickle chargers” have the ability to detect the voltage level and automatically adjust the amps delivered.

In a totally dead battery, the smart trickle charger delivers more power but slows down as it approaches a full charge. This makes it possible for a smart trickle charger to be connected indefinitely without the risk of overcharging just like a battery tender. There is therefore not much difference between a battery tender and a smart trickle charger.

Can A Trickle Charger Charge Dead Car Batteries?

Definitely! The alternator of a car is responsible for maintaining a healthy battery, but it can’t recharge a dead battery. But, a trickle charger definitely could charge a dead battery. Although it will take a long time for it to bring a dead battery to an acceptable level of charge. Charging a dead 12-volt battery with a trickle charger that delivers from 1 to 3 amps of power only will take from around 20 to 24 hrs.before it reaches a reasonable charge, according to the experts. This is because a car battery is ordinarily 48 amps and takes an average of around 1 amp charge per hour.

Of course, the main purpose of a trickle charger is to ensure that a battery is kept alive when not in use for a long period of time even when it is self-discharging. Still, it can bring to life a dead battery as long as the battery is in good condition and not thoroughly worn out.