12V 12Ah Lead-Acid and Lithium Rechargeable Batteries

12V 12Ah lead-acid and lithium batteries are highly popular deep-cycle rechargeable batteries often used for powering UPS devices, security systems, medical equipment, toys, scooters, and other smaller electric vehicles, fish finders, and similar.

12V 12Ah batteries are relatively compact devices and with the introduction of Lithium Iron Phosphate (LiFePO4) batteries, very lightweight batteries that support a large number of charging/discharging cycles. But, Sealed Lead-Acid (SLA) 12V 12Ah batteries are still in demand due to their certain advantages over lithium counterparts.

Updated: April 24, 2023.

On This Page:

• 12V 12Ah Batteries Dimensions and Chemistries
• Battery Cross Reference Chart
• How to Charge 12V 12Ah Battery
• Frequently Asked Questions (FAQ)
• Few Final Words 

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12V 12Ah Batteries Dimensions and Chemistries

12V 12Ah batteries feature physical dimensions of (L x W x H) ~5.94 x 3.86 x 3.74 inches (~151 x 98 x 95 mm) and are designed and built as deep cycle batteries and should be used as such.

If You are looking for similar starting batteries, check our Powersports, ATV, and Motorcycle Battery Cross Reference Chart page.

Most popular 12V 12Ah battery chemistries include lead-acid and lithium batteries, although other chemistries are used as well, although rarely, for example, Nickel Cadmium (NiCd) and Nickel Metal Hydride (NiMH).

12V 12Ah batteries usually come with F2 battery terminals, although sometimes other terminals are used as well, for example, M6 battery terminal.

Lead Acid 12V 12Ah Batteries

Lead-acid 12V 12Ah batteries are mostly sealed, maintenance-free Absorbent Glass Mat (AGM) and Gel-Cell batteries, with flooded/wet 12V 12Ah deep-cycle lead-acid batteries being obsolete.

Lead acid 12V 12Ah batteries feature a nominal voltage of 12V and a nominal capacity of 12Ah, they weigh ~7.3-8.0 pounds (~3.3-3.6 kg) and are popular in standby devices that don't cycle too often but need a compact battery that is able to provide 2C+ currents continuously.

Note: when the lead-acid batteries are discharged with 0.5C and stronger currents, their actual capacity drop is significant. For example, 12V 12Ah batteries feature a nominal capacity of 12Ah (when being discharged for 20h!), but only ~7-7.3Ah when being discharged for one (1) hour.

The number of charging/discharging cycles greatly depends on the Depth of Discharge (DoD%) - most AGM 12V 12Ah batteries are able to withstand:

• 160-220 cycles down to 100% DoD,
• 320-420 cycles down to 50% DoD,
• 800-950 cycles down to 30% DoD.

These numbers differ from battery to battery and must be checked for each battery individually. However, they don't differ much.

If the battery is used in an, for example, UPS that is activated at most a few times per year, a good AGM 12V 12Ah battery can last for years if its temperature is kept low (up to 20-25°C) and the UPS maintains the battery's charge properly.

Modern AGM batteries feature a relatively low self-discharge rate, and most AGM 12V 12Ah batteries, when stored at room temperature, can be kept for up to 3 months without adverse effects on the battery.

If they are going to be stored for a longer period of time, they should be connected to an intelligent battery charger/maintainer with a temperature probe that will keep the batteries fully charged during storage.

When connecting lead-acid 12V 12Ah batteries in series and parallel, feel free to connect them as recommended by their manufacturers - use the very same batteries (preferably from the same batch), charge them to the exactly the same voltage (charge them fully, if possible) and connect them as required.

Lithium 12V 12Ah Batteries

Lithium 12V 12Ah batteries are a newer type of battery and are based almost exclusively on Lithium Iron Phosphate (LiFePO₄) chemistry.

LiFePO₄ batteries feature a nominal cell voltage of 3.2V, and with four (4) cells internally connected in series, they feature a nominal voltage of 12.8V with a charging voltage usually in the 14.4-14.6V range.

For lithium batteries to be safe, they must feature a built-in Battery Management System (BMS) that monitors the battery condition and protects the battery from unwanted events like overcharge, over-discharge, low and high temperature, overcurrent, and similar.

The charging voltage of lithium batteries is very similar to the charging voltage of AGM batteries, but often a few hundred mVs higher - this means that drop-in lithium battery replacements can be used to replace similar AGM batteries, but in such applications, these batteries are usually recharged up to 85-90% of their nominal capacity.

So, if possible, charge them using dedicated lithium battery chargers or AGM battery chargers that feature dedicated lithium battery charging modes.

Note: Lithium-Ion and Lithium-Polymer chemistries with 3.6-3.7V per cell are rarely used in 12V 12Ah deep-cycle batteries - these chemistries are more often used in starting batteries and deep-cycle batteries that must provide huge currents (drones, RC models, and similar).

Lithium Iron Phosphate batteries feature numerous advantages and some disadvantages over lead-acid batteries, including:

• they don't suffer from capacity loss when they are discharged with relatively strong currents, at least not nearly as lead-acid batteries. For example, a 1h capacity of the lithium 12V 12Ah batteries is almost 12Ah, with many models featuring a 1h capacity of 12Ah, which is a great improvement over the 7.0-7.3Ah 1h capacity of the lead-acid batteries.
• maximum continuous discharge current is usually around 1C (12 Amps), with some models supporting somewhat stronger currents for very short periods of time. On the other hand, lead-acid 12V 12Ah batteries often support 120-180 Amps for 5-10 seconds and ~40 Amps for 5 minutes.

• lithium 12V 12Ah batteries support 2000+ charging/discharging cycles down to 80-100% DoD, which is 8-10x more than lead-acid batteries.
• lithium 12V 12Ah batteries are at least 2x lighter than lead-acid batteries. However, if the capacity loss is taken into account when the batteries are discharged in the period of 1-2 hours, lithium batteries are actually 3-4x lighter than lead-acid batteries.
• lithium 12V 12Ah batteries cannot be connected in series/parallel freely - they MUST be connected in parallel and/or series only if explicitly allowed by their manufacturers and MUST be connected as recommended by their manufacturers. When connecting them in parallel and/or series, always use the batteries from the same manufacturer, preferably from the same batch, and connect them as allowed.
• If allowed, lithium 12V 12Ah batteries may be connected from 4S2P to 4S4P configuration (up to 48V and up to 24-48Ah).
•  lithium 12V 12Ah batteries accept the charge better than lead-acid batteries and can be recharged on average 2-4x faster.

Although lithium batteries have certain drawbacks regarding charging, output current, and parallel/series configurations, they do offer many benefits - if You are looking for a lightweight 12V 12Ah battery that cycles well, go for lithium batteries. After all, thanks to advancements in technology, some lithium batteries in this class feature a nominal capacity of 18Ah, which is 50% more that a standard nominal capacity for the batteries in this group.

One of these batteries is a Dakota Lithium 12V 18Ah LiFePO4 Deep Cycle Battery (Amazon link, link opens in the new window), which is one of the best overall batteries in this class.

 

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Battery Cross Reference Chart

The following battery cross-reference chart lists some of the most popular lead-acid and lithium 12V 12Ah batteries that feature physical dimensions of (L x W x H) 5.94 x 3.86 x 3.74 inches (~151 x 98 x 95 mm).

When choosing the right battery, choose according to your own needs and requirements.

Obviously, lithium 12V 12Ah batteries offer larger actual capacity when discharged with currents up to 1C, but their BMSs may be sensitive to over-discharge conditions and may disconnect the battery in such conditions - for such situations, lead-acid 12V 12Ah batteries are IMHO more reliable power sources.

But, for currents up to 8-12 Amps (battery dependent), 12V 12Ah lithium batteries are lighter batteries that accept charge faster and support a much larger number of charging/discharging cycles.

 

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How to Charge 12V 12Ah Battery

When the 12V 12Ah battery is part of a larger system that features a built-in battery charger (for example, an UPS), let that built-in charger do its task and charge the battery.

When the 12V 12Ah batteries are charged on the bench, for example, one should use an advanced battery charger with the battery charging mode depending on the battery type (AGM, Gel-Cell, LiFePO₄), battery use (standby, cycle use), and temperature (temperature sensor is highly recommended).

The maximum charging current for lead-acid 12V 12Ah batteries are around 3-3.5 Amps, with 2 Amps chargers being highly recommended.

For example, when the lead-acid 12V 12Ah battery is discharged down to 50% DoD, then the 2 Amps battery charger can fully recharge the battery in 3-4 hours.

The maximum charging current for lithium 12V 12Ah batteries is around 6-12 Amps, with 3-6 Amps chargers being recommended - again, this depends on the individual battery and how heavy the battery cycles.

Note: When charging lithium 12V 12Ah batteries, either use a dedicated lithium battery charger or AGM advanced battery charger with a dedicated lithium battery charging mode.

 

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Frequently Asked Questions (FAQ)

Here are some of the most common Frequently Asked Questions (FAQ) about 12V 12Ah lead-acid and lithium rechargeable deep-cycle batteries:

What Does 12V 12Ah Mean?

12V 12Ah means that the battery features a nominal voltage of 12V and a nominal (20h) capacity of 12 Ah - the battery is able to provide 0.6A for 20h.

Actual voltage and capacity vary depending on battery age, temperature, load, charge condition, etc.

How Long Will a 12V 12Ah Battery Last?

"How Long Will a Battery Last" may refer to:

• a number of charging/discharging cycles: lead-acid 12V 12Ah batteries may last up to or even more than 150-220 cycles down to 100% DoD, while lithium 12V 12Ah batteries may last up to or even more than 1500-2000 cycles down to 100% DoD.
• standby use: when being used at room temperatures and properly charged, lead-acid batteries feature a standby operating life of 2-5 years, sometimes a little bit more. Under the same conditions, lithium batteries may last up to 10+ years, model dependant!
• under a certain load: when providing a certain current, for example, 7 Amps, 12V 12Ah lead acid batteries may last ~1h, while under the same load 12V 12Ah lithium batteries may last up to 100 minutes. However, if the current goes above 12A continuously, most lithium 12V 12Ah batteries will simply shut off, while lead-acid batteries will continue to operate for some time.

Can You Overcharge a 12-Volt Battery?

Yes,  12V 12Ah batteries may be overcharged - that is why intelligent battery chargers with required charging battery modes and temperature sensors are highly recommended...

What Watt Solar Panel Do I Need For a 12V 12Ah Battery?

12V 12Ah batteries are charged with voltages up to 15V (actually 14.2-14.6 volts for most batteries, but for the sake of simplicity let's assume 15V) and currents between 2 and 12 Amps - 2-3 Amps lead-acid batteries and 3-12 Amps lithium batteries.

Assuming 50% energy efficiency of the solar panel/solar battery charge controller combination, that means that the solar panel must feature between 60W (charging up to 15V, 2A) and 360W (charging up to 15V, 12A).

Note: energy efficiency of solar panels depends on the solar panel orientation, season, weather, and similar, while most solar battery charge controllers feature energy efficiency in the 80-90% range, meaning that the energy efficiency of 50% for such a combination is a real-life value.

How Long Does It Take To Charge a 12V 12Ah Battery Fully?

Charging time depends on the Depth of Discharge (DoD%), charging current, and battery condition.

If the 12V 12Ah battery is in good condition and discharged down to 80% DoD (2.4Ah remaining), a lithium battery that may be recharged with, for example, 6 Amps, can be recharged in less than two hours.

A similar lead-acid battery that is charged on average with 2 Amps can be recharged in 5-6 hours.

What Are The Dimensions of a 12V 12Ah Battery?

12V 12Ah batteries feature physical dimensions of (L x W x H) ~5.94 x 3.86 x 3.74 inches (~151 x 98 x 95 mm).

How Long Will an 18W Light Run Off a 12V 12Ah Battery? How Many Watts Does a 12 Volt Battery Put Out?

How long can a 12V 12Ah battery provide 18W or any other wattage, depends on the battery model.

For example, the following chart lists the constant power discharge of the ExpertPower 12V 12Ah EXP12120 AGM battery:

Constant Power Discharge (Watts) at 77°F (25°C)
Volts/Cell	Volts/Battery	5 min	10 min	15 min	30 min	1h	2h	3h	4h	5h	6h	10h	20h
1.85V	11.1V	461.64	272.52	214.14	139.62	81.48	47.10	36.18	29.70	24.36	19.86	13.02	6.78
1.80V	10.8V	470.40	277.68	218.28	142.26	83.04	48.00	36.84	30.24	24.78	20.22	13.26	6.90
1.75V	10.5V	479.22	282.90	222.36	144.96	84.60	48.90	37.56	30.84	25.26	20.58	13.50	7.02
1.70V	10.2V	522.36	299.88	235.68	150.72	86.10	49.74	38.22	31.38	25.74	20.94	13.74	7.14
1.65V	9.9V	575.10	325.32	255.72	159.12	87.00	50.28	38.64	31.74	25.98	21.18	13.92	7.20
1.60V	9.6V	623.04	342.30	269.04	165.96	87.96	50.82	39.06	32.04	26.28	21.42	14.04	7.32

Theoretically, a 12V 12Ah battery may provide 1.5A for 8 hours @12V, but in real life, as the battery is discharged, its voltage drops.

Since 1.5 Amps is not too strong of a current for lead-acid and lithium 12V 12Ah batteries, one may safely assume that a new, fully charged 12V 12Ah lead-acid battery can provide 18W for 7+ hours, while a similar lithium battery can provide 18W for almost 8 hours.

What is the difference between 12V 7Ah and 12V 12Ah?

There are several key differences between 12V 7Ah and 12V 12Ah batteries:

• nominal capacity: 12V 7Ah batteries feature a nominal (20h) battery capacity of 7Ah, while 12V 12Ah batteries feature a nominal (20h) capacity of 12Ah.
• dimensions: 12V 7Ah nominal dimensions are (W x L x H) 5.94 x 2.56 x 3.7 inches, while 12V 12Ah nominal dimensions are 5.94 x 3.86 x 3.74 inches.
• terminals: most older 12V 7Ah batteries feature F1 battery terminal, while newer AGM and lithium 12V 7Ah batteries feature F2 battery terminal. 12V 12Ah batteries feature almost exclusively an F2 battery terminal, with only just a few models coming with M6 battery terminals.

Due to these differences, 12V 12Ah batteries store more energy and may provide more power than 12V 7Ah batteries.

 

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Few Final Words

 

12V 12Ah batteries are offered as lead-acid and as lithium batteries. If your application requires batteries that cycle well and the batteries don't have to provide more than 1C, go for lithium batteries.

For standby applications where battery weight and the number of supported cycles are not that important, lead-acid batteries may be the preferred choice, since they are not sensitive to the overload conditions like lithium batteries which may be turned off by their BMS if the overload condition is met - and that is usually in the most critical moments ;)