Flooded Lead Acid Batteries

What is a deep cycle battery?

Trojan’s lead acid flooded batteries, AGM batteries, and AES AGM batteries are deep cycle batteries. Deep cycle batteries are designed for repeated discharging and recharging, making them suitable for applications where the battery is frequently used and depleted.

Deep cycle batteries are ideal for applications requiring continuous power over extended time periods, especially golf cars, marine and boating, RVs, and solar. Only deep cycle batteries should be used in renewable energy applications.

Trojan flooded batteries can withstand frequent and repeated charging and discharging. This deep cycling ability makes them ideal for applications that require heavy usage and reliability.

Flooded lead acid vs. AGM batteries

Lead acid batteries are generally classified by application (what they are used for) and by construction (how they are made).

Two popular construction types are: flooded batteries (wet or wet cell) and VRLA batteries (Valve Regulated Lead Acid). Trojan manufacturers deep cycle batteries in both flooded and AGM lead acid models.

In flooded lead acid batteries, the electrolyte is a solution of sulfuric acid and water. It can spill out if the battery is tipped over.

In VRLA batteries, the electrolyte is suspended in a fiberglass mat (AGM and AES AGM technology), allowing these batteries to be mounted in a variety of positions.

How far can I tilt my batteries?

For flooded batteries, 22 degrees from vertical is the maximum recommended tilt. AGM batteries can be operated vertically or horizontally.

More about comparing flooded batteries to AES AGM and lithium batteries >

Choosing a flooded lead acid model

When choosing your flooded battery model, first consider your battery compartment space, as this may limit your options.

Within your size restrictions you may have several battery options to choose from. For example, you can use T-605, T-105, or T-125 flooded batteries in the same space, as they are the exact same physical size. You can find battery dimensions on the product page or in the product's datasheet.

The difference between these batteries is the amount of energy they offer. Consider your energy needs. If you are replacing an existing battery, use it as a reference point.

If your old battery provided enough energy, it can be replaced with a similar capacity battery. If you need more energy you can size up, If you need less energy you can size down.

Use the Battery Finder to identify replacement battery options for your equipment or vehicle >

The differences between deep cycle batteries, starting batteries, and dual-purpose batteries

A deep cycle battery can be deeply discharged and charged many times during its service life. It is designed specifically for powering electrical equipment for long periods of time.

An automotive or starting battery is designed for brief bursts of high current. It cannot withstand more than a few deep discharges before failure. This is why you can't start your car if you accidentally leave the lights on more than a few times.

For applications where both engine starting and light deep cycling are required, a dual-purpose battery is often used. This type of battery is neither a starting nor a deep cycle battery but rather a compromise between the two that allows it to perform both functions adequately.

Understanding battery ratings and amp-hours

The 100-hour rate is an index used in the battery industry to compare batteries of different types and sizes. The 100-hour rate is the amount of Ampere-hours or Amp hours (Ahs) that a battery will deliver during a 100-hour discharge.

The capacity of a battery, in Ahs, is a dynamic number that is dependent on the discharge current. For example, a battery that is discharged at 10Ahs will give you more capacity than a battery that is discharged at 100Ahs.

With the 100-hr rate, the battery can deliver more Ahs than with the 20-hr rate because the 100-hr rate uses a much lower discharge current than the 20-hr rate.

Both rates are used as baselines in different parts of the world. Both rates, however, will give you the same view of a battery. A higher capacity battery will have higher 5- and 20-hour rates than a battery with lower capacity

Replacing flooded batteries in your equipment

Can I do a partial replacement of my flooded batteries?

We do not recommend the partial battery replacement of flooded battery banks.

The behavior of batteries during discharging and charging varies throughout their lifespan; if all the batteries are the same age, they all will have similar responses.

The danger with replacing only one battery is that the older batteries will tend to require more charge than the newer ones, and since the new batteries are in the same circuit, they will also be overcharged.

There is also the chance that the older batteries will be undercharged since the overall voltage response of all the batteries (old and new) will not be a good representation of either group. The charging system might erroneously detect that ALL the batteries have reached the desired voltage. This may cause the battery charging to stop before completed.

How do I find batteries that are compatible with my equipment?

Trojan’s Battery Finder online tool helps you find all the Trojan battery options for your golf cart, floor scrubber, industrial equipment, and other battery-powered machinery.

Look up your equipment’s manufacturer and model in the Trojan Battery Finder >

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