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Guide of 8D Deep Cycle Battery: AGM VS Lithium

May 23, 2024

When choosing 8D batteries, many people are unable to start because they do not understand the product.

The 8D battery is one of the largest RV and marine batteries available, a large battery that is critical to ensuring optimal performance and longevity. 8D pack batteries are often preferred due to their superior power output and reliability.

This article will take you through what an 8D battery is, its specific application scenarios, and the specific advantages of using 8D lithium batteries to replace 8D lead-acid batteries. Hope this blog can help you.

What is an 8D Battery?

8D batteries are a size of deep-cycle battery commonly found in large vehicles such as boats and RVs, heavy machinery, and off-grid power systems. The battery industry develops battery pack sizes to help people determine what size battery they need. These batteries are known for their robust construction, capacity and high starting current, making them suitable for demanding tasks such as starting diesel engines and providing continuous power for long periods of time.

The Dimension of 8D Battery

The 8D pack battery has approximate dimensions of approximately 21 inches x 11 inches x 10 inches (length x width x height), making it one of the largest 12-volt batteries available to consumers. The large size of the lead-acid 8D battery allows for more, thicker lead plates inside. The added plates provide greater capacity and higher starting current compared to other battery packs.

redodo 8d battery dimensions

Applications of Group 8D Battery

8D batteries are commonly used in a variety of applications that require high power and capacity. Some of the common applications include:

  1. Heavy machinery: 8D batteries are often used in construction equipment, such as excavators, bulldozers, and cranes, due to their ability to provide the necessary power for these demanding applications.
  2. Motorhomes and RVs: 8D batteries are frequently used in motorhomes and RVs as they offer a robust power source for running appliances, lights, and other electrical systems while off-grid.
  3. Commercial trucks: Many commercial trucks, including semi-trucks and delivery trucks, rely on 8D batteries to provide the necessary power for starting the engine and operating various electrical components.
  4. Marine applications: 8D batteries are commonly used in boats and marine vessels to power the onboard systems, such as lighting, navigation equipment, and auxiliary engines.
  5. Industrial backup power systems: Due to their high capacity and power output, 8D batteries are suitable for industrial backup power systems, providing a reliable source of power during outages or emergencies.
  6. Agricultural equipment: Tractors and other agricultural machinery often employ 8D batteries to power the engine and electrical systems required for farming operations.
  7. Off-the-grid Power Systems: 8D batteries are commonly used to build solar battery banks for cabins, tiny homes, or off grid houses. The high capacity is optimal for storing large amounts of energy produced by solar panels. For greatest efficiency the Redodo LiFePO4 battery is highly recommended for off grid and solar applications. This is because Redodo battery has a 95% efficiency rate vs 70% for lead acid. This means you get to use more of the energy created by your solar panels.

The Weight of 8D battery

Traditional 8d batteries typically weigh between 120 and 180 pounds, which is quite heavy, and have a capacity of 230 to 300 amp hours. Speaking of recent popular new lithium batteries, they have a great advantage in weight, such as Redodo 24V 200Ah Deep Cycle 8D Lithium Battery, weighing at 85.54 lbs. One person can carry them while providing twice the available power. The following will introduce in detail the advantages of Redodo 8D lithium battery and the reasons why it can be replaced.

Benefits of 8D Lithium Battery

8D lithium batteries are a relatively recent addition to the market, offering several advantages over traditional lead-acid batteries. Typically, lithium 8D batteries have a lower current limit, around 500 amps. However, specific models, such as Redodo’s 8D lithium battery, can handle short current surges exceeding 500 amps for durations up to half a second.

1. Weighs Much Less than 8D Lead-Acid

Generally, lithium batteries weigh roughly half as much as lead-acid batteries with similar capacities, and 8D lithium batteries are no exception. For instance, our Redodo 8D lithium battery weighs only 85.54 pounds but offers the same capacity as three lead-acid 8D batteries or nine lead-acid 100Ah batteries. This results in a weight saving of 460 pounds. 8D batteries are commonly used as RV house batteries, and moving a 200-pound battery can be quite difficult.

2. Great for Large Marine or Large Off-Grid Applications

Redodo 8D lithium battery does not have CCA function, but it has excellent deep cycle discharge capability. Discharging a lead-acid deep cycle battery below 50% of its capacity causes damage and shortens its lifespan. In contrast, lithium batteries can be discharged to over 80% of their capacity without any damage. This increased efficiency makes lithium batteries an excellent choice for replacing lead-acid batteries in marine and large off-grid applications.

3. Charges 5 Times Faster than Lead Acid

Lithium batteries not only provide greater efficiency compared to lead-acid batteries, but they also charge significantly faster. With the right charge controller, a lithium battery can charge up to five times quicker than a comparable lead-acid battery.

Built-in 200A Battery Management System (BMS)

Advantages to Replacing 8D Batteries with Lithium

Compared with AGM 8D batteries, 8D lithium batteries revolutionize power solutions for boat and RV owners. The Redodo 24V 200Ah LiFePO4 Battery, an 8D equivalent, offers a 5120Wh capacity while weighing only 85.54 pounds. The advantages of the Redodo 24V 200Ah LiFePO4 battery over traditional AGM 8D batteries include:

  • Lightweight. Traditional 8d battery weighs between 120 and 180lbs. Redodo LiFePO4 Lithium Battery weighs 85.84lbs, which is lighter than lead-acid batteries.
  • 5120Wh Higher Energy. A 24V 200Ah lithium battery is equivalent to two 24V 100Ah lithium batteries. It can be expanded to a maximum configuration of 2S4P, creating a 51.2V 800Ah battery system with approximately 41kWh of energy. This makes it ideal for applications that require higher power or longer battery runtime. The battery has a flat voltage curve, giving you a more stable charge than lead-acid batteries.
  • Stong & Robust BMS. With Redodo's high-quality Battery Management System (BMS), you can be confident that your battery is fully protected against overvoltage, undervoltage, overheating, overcurrent, and short circuits. This advanced system guarantees exceptional reliability and safety for your battery.

Built-in 200A Battery Management System (BMS)

  • 10-Year Lifetime. The 24V LiFePO4 battery can realize 100% SOC&DOD and has a 10-year service life, three times longer than the Lead Acid’s 3-year.
  • 4000-15000 Deep Cycle. 24V 200Ah lithium battery can run 4000~15000 cycles, which is more than 10 times Lead Acid with 200~500 cycles.

Redodo 8d deep cycle battery

  • Maintenance-Free. Lithium batteries are typically maintenance-free, unlike AGM batteries which require regular upkeep, including checking electrolyte levels and ensuring proper ventilation.
Aspect AGM 8D batteries Lithium Batteries (LiFePO4)
Weight 120 to 180 lbs 85.84 lbs
Energy Capacity Limited expansion, lower energy density expandable up to 41kWh
Battery Management System (BMS) Basic protection features Advanced BMS with protection against overvoltage, undervoltage, overheating, overcurrent, and short circuits
Lifetime Approximately 3 years 10 years 
Cycle Life 200-500 cycles 4000-15000 cycles
Maintenance Requires regular maintenance (e.g., checking electrolyte levels, ensuring proper ventilation) Maintenance-free

Redodo 24V 200Ah LiFePO4 Battery

Are 8D Batteries Worth It?

8D batteries provide greater capacity and power with reduced weight and footprint compared to using three smaller lead-acid batteries. Depending on your application and power requirements, these large batteries can be an excellent choice, particularly in a lithium version.

The main disadvantage of these large batteries is their significant weight, making them more difficult to maneuver than smaller batteries. However, upgrading to a lithium 8D battery offers even greater capacity than a lead-acid 8D battery while maintaining a weight similar to a smaller lead-acid battery with only a third of the capacity. Additionally, a lithium 8D battery is likely to last much longer, minimizing the need for replacements and providing cost savings and reliability over its lifespan.

For Power Storage Go Lithium

8D batteries are larger and heavier, offering more power and capacity than other battery types. They are an excellent option for replacing a series of smaller batteries in large applications with high power requirements. Moreover, with the advent of lithium 8D batteries, you can enjoy the benefits of traditional lead-acid batteries without the extra weight, plus a lifespan of over 10 years. Explore our industry-leading lithium 8D batteries to see if they are the right choice for you.

FAQs about 8D Battery

1. What does 8D mean on a battery?

Batteries are categorized by “groups” based on their physical size. The group 8D battery is one of the largest batteries available to use. The group 8D battery dimension is about L21*W11*H10 inch.

2. What's the difference between a 4D and an 8D battery?

The main differences are that the 4D battery is slightly smaller than the 8D, has a bit less deep cycle capacity, weighs slightly less, and has lower cold cranking amps.

3. How long should an 8D battery last?

Lithium 8D batteries typically last for 4,000 to 15,000 cycles, whereas lead-acid batteries only last for 200 to 500 cycles. Additionally, lithium 8D batteries require less maintenance than lead-acid batteries.

4. Is this 8D battery a deep cycle battery?

Redodo 24V 200Ah LiFePO4 battery is a 8D deep cycle battery, widely used in RVs, marine, home storage and off-grid.

5. Can I use Redodo LiFePO4 Lithium batteries as starting batteries?

No. Redodo LiFePO4 battery is used as energy storage, but not intended to be used as starting batteries. Lithium group 8d also does not have CCA startup function. You can read the following article which will be helpful to you: Deep Cycle VS Starting Battery


Overall, the 8D battery is a staple of the lead-acid battery industry, designed to provide more power through a larger size. For heavy-duty applications, selecting the right 8D battery pack is crucial for ensuring smooth and reliable operation.

Choosing a high-quality 8D battery pack not only enhances performance but also offers longevity and peace of mind for years. With Redodo LiFePO4 batteries, there's no need to install a 200-pound lead-acid battery in your boat or RV. Play harder, last longer, and go further with Redodo lithium batteries.