Battery Equivalents and Replacements

ExpertPower EXP12180 12V 18Ah AGM Battery

ExpertPower EXP12180 is a very popular and well-balanced AGM lead acid battery, featuring a nominal voltage of 12 volts and a nominal 20h capacity of18 Ah. It is a Sealed Lead Acid (SLA) Absorbent Glass Mat (AGM) battery with a battery case made of ABS plastic, very resistant to mechanical shocks and impacts, vibrations, chemicals, and heat.

ExpertPower EXP12180 is designed to be used in cycling and floating applications, with float life span of 3 to 5 years. In cycling applications, it is commonly used in various toys, electric vehicles, as small solar and general off-the-grid battery and similar. And it comes at very acceptable price.

All these are reasons why ExpertPower EXP12180 is one of the most popular batteries in its class.

Updated: May 14, 2024.

expertpower exp12180 1

ExpertPower EXP12180 AGM Battery - Features and Specifications

As an AGM battery, ExpertPower EXP12180 is a practically maintenance-free battery with a very low self-discharge rate, especially at lower temperatures.

The physical dimensions of the battery are (L x W x H) 7.12 x 3.03 x 6.57 inches (~18.1 x 7.7 x 16.7 cm), and it weighs 11.68 pounds (~5.3 kg).

Fully charged ExpertPower EXP12180 battery features internal resistance of ~12 mΩ, measured at 77°F (25°C).

The maximum charging current is 5.4 Amps, enabling the user to charge the battery rather fast, although charging currents around 2 Amps are recommended for the 'bulk' charging phase.

The charging voltage at 77°F (25°C) for cycling use is in the 14.4 - 15.0 volts range (-30mV/°C), and for float use, the charging voltage is in the 13.5 - 13.8 volts range (-20mV/°C).

Note: personally, I don't like the idea of charging AGM batteries above 14.8 volts (at 77°F/25°C).

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ExpertPower EXP12180 features M5 Bolt & Nut terminal posts. When the battery is charged and maintained with an intelligent 2-3 Amps AGM battery charger, the only actual maintenance task is checking from time to time if there is corrosion on the terminals and connecting wires (it rarely happens, but check just in case).

The self-discharge rate is low and it depends on the storage temperature:

  • 104°F (40°C): ~40 days down to 80% SoC, ~2 months down to 70% SoC, ~3 months down to 60% SoC,
  • 86°F (30°C): ~50 days down to 80% SoC, ~100 days down to 70% SoC, ~6 months down to 60% SoC,
  • 77°F (25°C): ~3 months down to 80% SoC, ~6.5 months down to 70% SoC, ~10 months down to 60% SoC,
  • 41°F (5°C): ~2 months down to 90% SoC, ~10 months down to 80% SoC, ~20 months down to 70% SoC.

As one can see, as the storage temperature drops, the self-discharge rate drops significantly. When storing AGM batteries, it is good practice not to let them discharge below 80% SoC (or 20% DoD).

ExperPower EXP12180 AGM Battery Discharge Characteristics

ExperPower EXP12180 AGM battery behaves similarly to all other AGM batteries - as the discharge current is increased, actual capacity drops:

  • 20 hr capacity (0.90 Amps, down to 10.5 volts, at 77°F/25°C): 18 Ah,
  • 10 hr capacity (1.73 Amps, down to 10.5 volts, at 77°F/25°C): 17.3 Ah,
  • 5 hr capacity (3.24 Amps, down to 10.5 volts, at 77°F/25°C): 16.2 Ah,
  • 1 hr capacity (10.85 Amps, down to 10.5 volts, at 77°F/25°C): 10.85 Ah.

Increasing the discharge current even more, leads to even more drop in actual capacity - again, this is feature of all lead acid batteries, not just ExperPower EXP12180 battery.

The following chart shows the constant current discharge characteristics of the ExpertPower EXP12180 battery.

Values are given in Amps, measured at 77°F (25°C):

V/Cell V/Battery 5 min 10 min 15 min 30 min 1 hr 2 hr 3 hr 4 hr 5 hr 6 hr 10 hr 20 hr
1.85 11.1 59.18 34.94 28.46 17.90 10.45 6.04 4.64 3.808 3.120 2.544 1.668 0.867
1.80 10.8  60.31  35.60  28.98  18.24  10.65  6.15  4.73  3.880  3.180  2.592  1.700 0.882
1.75 10.5  61.44  36.27  30.51  18.58  10.85  6.27  4.81  3.953  3.239  2.641  1.732  0.900
1.70 10.2  66.97  38.45  32.22  19.32  11.04  6.38  4.90  4.023  3.296  2.687  1.762  0.916
1.67 10.02  73.73  41.71  34.78  20.40  11.15  6.45  4.95  4.066  3.332  2.716  1.781  0.926
1.60 9.6  79.87  43.89  35.90  21.28  11.27  6.52  5.00  4.110  3.368  2.745  1.800  0.936

Similarly, the following chart shows the constant power discharge characteristics of the ExpertPower EXP12180 battery.

Values are given in watts, measured at 77°F (25°C):

V/Cell V/Battery 5 min 10 min 15 min 30 min 1 hr 2 hr 3 hr 4 hr 5 hr 6 hr 10 hr 20 hr
1.85 11.1 692.4 408.7 321.2 209.4 122.2 70.6 54.2 44.6 36.5 29.8 19.5 10.14
1.80 10.8  705.7 416.6  327.4  213.4  124.6  72.0  55.3 45.4  37.2 30.3 19.9  10.32
1.75 10.5  718.9  424.4  333.5  217.4  126.9  73.3  56.3 46.2  37.9  30.9  20.3  10.56
1.70 10.2  783.5  449.8  353.5  226.1  129.1  74.6  57.3  47.0  38.8  31.4  20.6  10.74
1.67 10.02  862.6  488.0  383.6  238.7 130.5  75.4 58.0  47.6  39.0  31.8  20.8  10.86
1.60 9.6  934.6  513.5  403.6  248.9  131.9  76.2  58.6  48.1 39.4  32.1  21.1  10.92

When the ExpertPower EXP12180 battery is being discharged for longer than ~40 minutes, the gain in the delivered power by discharging the battery to the lower end voltage is not significant.

For example, when the battery is being discharged for 5 hours with the end voltage of 11.1 vs 9.6 volts, power difference is ~7.4%.

But, when the battery is being discharged for 30 minutes or less, battery power can be increased by ending the discharge process with lesser battery voltage.

For example, when the battery is being discharged for 5 minutes with the end voltage of 11.1 vs 9.6 volts, power difference is ~26%.

Reason why this can be done lies in the AGM chemistry - when the AGM battery is being drained quickly, it can be, more or less safely, discharged down to 9.6 volts instead of 10.5 volts.

10.5 volts value is generally accepted 'safe' voltage below which one should not drain the AGM batteries, but when AGM batteries are drained faster, EXP12180 battery included, it can be drained to lower voltages.

Note: whenever the lead acid battery is discharged down to 20% DoD (80% SoC) or less, charge it right away - such charging can prolong the operating life of AGM batteries significantly, especially when the batteries are charged with smart AGM battery chargers.

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ExpertPower EXP12180 Service Life

When the ExpertPower EXP12180 is used in float applications, its service life is 3-5 years, depending on the operating temperature.

When th ExpertPower EXP12180 battery is used in deep cycling applications, its operating life (number of cycles) depends mostly on the depth of discharge (DoD):

  • 100% DoD: capacity drops down to 80% after ~180-205 cycles, capacity drops down to 60% after ~190-260 cycles,
  • 50% DoD: capacity drops down to 80% after ~330-410 cycles, capacity drops down to 60% after ~405-510 cycles,
  • 30% DoD: capacity drops down to 80% after ~800-920 cycles, capacity drops down to 60% after ~1060-1215 cycles.

In order to increase the number of charging/discharging cycles, don't fully discharge the battery.

 ExpertPower EXP12180 AGM Battery as Fish Finder Battery

ExpertPower EXP12180 can be used as an excellent and cheap fish finder battery in small boats, kayaks and similar vessels that don't have their own electric system.

Most fish finders consume around or less than 1 Amp of current, when powered from 12V sources. Smaller, portable models draw even less than that, but larger ones, especially fish finder/GPS combos can draw more than that.

garmin striker mFor example, one of the most popular, compact, and rather versatile fish finders Garmin Striker 4 GPS Fish Finder (Amazon link, opens in the new window), draws ~0.23 Amps when being powered with a 12V source.

When the ExpertPower EXP12180 is being used for powering such device, user can expect at least 78 hours (more than 3 days) of constant operation, which can be important on fishing trips away from suitable power sources that can be used to charge fish finder batteries.

When the EXP12180 is being used for larger fish finder/GPS combo devices that draw, for example, 3 Amps, one can expect that this battery can power such devices for at least 5 hours.

If you are looking for a good fish finder battery that can be used for other purposes as well, consider ExpertPower EXP12180 battery.

ExpertPower EXP12180 AGM Battery as Trolling Motor Battery

ExpertPower EXP12180 is not a recommended trolling motor battery, except for the smallest kayak trolling motors.

For example, Minn Kota Endura C2 Transom Mount Electric Trolling Motor features 30 pounds of thrust with the maximum current of 30 Amps.

ExpertPower EXP12180 is able to provide 30 Amps of power for ~15 minutes with the voltage not dropping below 10.5 volts.

However, trolling motors are rarely used at full throttle time, and if the power/current is reduced down to, for example, 18-19 Amps, ExpertPower EXP12180 can provide such current for ~30 minutes, with the voltage not dropping below 10.5 volts.

Unless you have a really small electric trolling motor and you don't need a long operating time, ExpertPower EXP12180 is not the best trolling motor battery for your needs.

ExpertPower EXP12180 AGM Battery for Off-the-Grid Applications

When being used for off-the-grid applications, the ExpertPower EXP12180 AGM battery can be easily charged with solar panels during the daylight.

During the period of 10h during the night, ExpertPower EXP12180 can provide ~20 W (~1.73 Amps) of power constantly, which can be enough to power for example, navigational LED lights, or marine radio, or some similar device.

If required, it can also be used for powering smaller flat screen TVs and smaller refrigerators, to be used for charging smartphones, tablets, laptops, etc; just be sure to monitor the battery's parameters like volts and current since such devices can be rather power-hungry and can quickly discharge the battery.

How to Charge ExpertPower EXP12180 AGM Battery

When the battery is used as a standalone unit, the best option is to use a smart, microprocessor-controlled AGM battery charger that can sense the battery condition and adapt the charging process to the battery being charged.

Also, such chargers are commonly used as battery equalizers and maintainers.

ExpertPower EXP12180 should be charged with a maximum current of 5.4 Amps, preferably with 2 Amps during the bulk charging phase. Smaller chargers (1 Amp charger, for example) can be used as well, although such chargers have longer charging times.

noco genius 2a charger

One of the recommended models is the NOCO GENIUS2 2A Smart Battery Charger (Amazon link, opens in the new window), which is a rather versatile battery charger, one of the most popular in its class. NOCO GENIUS2 is an advanced battery charger that can be used to charge various lead-acid 6V and 12V batteries and 12V LiFePO4 batteries.

Also, it can be used to recover deeply discharged batteries. And, after charging, it automatically switches to the maintenance mode and keeps the battery fully charged for a longer period of time.

To charge batteries at various temperatures properly, NOCO GENIUS2 also features a temperature sensor.

All in all, very interesting charger, not only for ExpertPower EXP12180 battery.

ExpertPower EXP12180 vs. ExpertPower EXP12200 Battery

expertpower12200 battery

ExpertPower EXP12200 is an AGM lead-acid battery very similar to ExpertPower EXP12180, except that it is slightly heavier (11.9 lbs, 5.4 kg vs. 11.68 lbs; 5.3 kg) and very often it costs slightly more.

But, ExperPower EXP12200 features a nominal capacity of 20Ah (@20h), which is ~5% more than the capacity of ExpertPower EXP12180, ensuring slightly longer runtime on a single battery charge.

Also, the maximum initial charging current is 6.0A vs. 5.4A - again, keep the charging current in the 2-3A range to avoid overstressing the battery.

Personally, these two batteries are so similar that you should go for either of them - whatever you find in your local hardware shop or online store. If you find both of them, and the price is very similar, go for ExpertPower EXP12200.

For more info about this battery, feel free to check the ExpertPower EXP12200 AGM Battery Amazon link (the link opens in the new window).


expertpower exp12180 mLong Story Short: ExpetPower EXP12180 is one of the best buy batteries and one of the most popular batteries in its class.

It is durable, it can power broad range of devices, it is rather affordable, tolerates deep discharges and is easily charged using rather cheap smart AGM battery chargers.

If you are looking for the general purpose 12V AGM battery in the 15-20Ah range, consider this one.

For more reviews and recommendations, check ExpertPower EXP12180 AGM Battery Amazon link (link opens in the new window).