The Best Group 51R, 51 Battery – Buyer’s Guide

When your car battery needs a replacement, choosing the right size is essential. Battery dimensions for Groups 51R and 51 are the same: 9.3 x 5.0 x 8.75 inches (Length x Width x Height), or 238 x 129 x 223 mm. The difference is only in terminal positions. A BCI group 51 and 51R are a common size for Japanese brands, such as Honda, Nissan, and Mazda. This review explores this common battery size and will help you decide which one will make the best 51 and 51R battery replacement for you.

Before we get started, you need to know that BCI group 51R and 51 batteries are the same size, capacity, and have similar electrical features, except for the positive battery terminal placement. On a group 51 battery, the positive terminal is on the left. On a group 51R battery, the “R” indicates that the positive terminal is on the right. It is possible to put either size battery in the car, as long as the battery terminal cables will reach. Sometimes you can rotate the 51 battery to make it work as 51R.

Now, let’s continue our exploration of the battery 51/51R for your car.

Best Choice

Duracell Ultra BCI Group 51R

The Best Group 51R and 51 Battery

This battery has 450 cold-cranking amps (CCA), which is enough to give you reliable starts, even in cold weather. Reasonable price and warranty for 36 months from Duracell.

Read Verified Customer Reviews

Before we dive deep into the reviews of various battery types, here is a quick comparison of the batteries in this review.

Image	Product
Good Price	SLI51R Duracell Ultra BCI Group 51R Car and Truck Battery Cold Cranking Amps (CCA): 450, Battery Group: 51R Type: Lead-Acid Warranty: 24 months Best for Heavy Electronics Check Price	Check Price
Good Choice	Optima Batteries 8073-167 D51R YellowTop Dual Purpose Battery Cold Cranking Amps (CCA): 450, Reserve Capacity (RC): 66, Amp-Hours (AH): 38 Battery Group: 51R Type: AGM Warranty: 36 months Best dual-purpose battery Check Price	Check Price
Cheapest	EverStart Maxx Lead Acid Automotive Battery, Group Size 51R (12 Volt / 500 CCA) Cold Cranking Amps (CCA): 500, Battery Group: 51R Type: Lead-Acid Warranty: 36 months Check Price	Check Price
Best Value	ACDelco Gold B24R Hybrid Vehicle AGM BCI Group 51 Battery Cold Cranking Amps (CCA): 325, Reserve Capacity (RC): 70, Amp-Hours (AH): 45 Battery Group: 51 Type: AGM Warranty: 24 months Best SLI Battery Check Price	Check Price
Also Great	Optima Batteries 8071-167 D51 YellowTop Dual Purpose Battery Cold Cranking Amps (CCA): 450, Reserve Capacity (RC): 66, Amp-Hours (AH): 38 Battery Group: 51 Type: AGM Warranty: 36 months Best Nissan Mazda 51 Battery Check Price	Check Price
Good Choice	Exide S51R Sprinter Classic 51R Battery 450 CCA Cold Cranking Amps (CCA): 450, Battery Group: 51R Type: Lead-Acid Warranty: 24 months Best Honda 51R Battery Check Price	Check Price
Good Choice	Megavolt Lead Acid Flooded Car Battery BCI 51R, 12V 55AH CCA500 CA525 (51R-60-500) Cold Cranking Amps (CCA): 425, Reserve Capacity (RC): 70, Amp-Hours (AH): 45 Battery Group: 51R Type: Lead-Acid Warranty: 24 months Best Affordable Option Check Price	Check Price
Good Choice	Duralast Gold Battery 51R-DLG Group Size 51R 500 CCA Cold Cranking Amps (CCA): 500, Reserve Capacity (RC): 85, Battery Group: 51R Type: Lead-Acid Warranty: 36 months Best for Cold Weather and Starting Check Price	Check Price

Quick Battery Comparison

The best place to determine if a 51R or 51 battery is right for your vehicle is to consult the Owner’s Manual. You should always choose a battery of the recommended size. If your vehicle requires a group 51 or 51R battery, this list should help you find one perfect for your needs.

1. Duracell Ultra BCI Group 51R — Best for Heavy Electronics

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Duracell is a household name in consumer electronics, but they are also known for the same reliability in their car batteries. They can easily supply the power needs of today's modern vehicles. This one has excellent starting power and maintenance-free for up to 24 months. Duracell makes its batteries to meet or exceed OEM specifications. Many times, they are better than the battery that came with the car when it was purchased. It has SAE posts, which provide a secure connection on most vehicles.

We recommend this battery because it has a reputation for long service life and can handle today's electronics. This battery's long life and reliability mean that it has a lower cost of ownership over time. It is well-sealed and maintenance-free with no need to check the acid levels.

• Brand known for quality

• Good for cold starts

• Made in the U.S.A.

• SAE Automotive Post

• Recyclable

• Lead-acid batteries not as long-lived as AGM

2. Optima Battery 8073-167 D51R YellowTop Dual Purpose — Best dual-purpose battery

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Optima is a good choice for those who need a durable battery that is reliable when it comes to starting. The Optima YellowTop is a good dual-purpose battery with both cranking power and can withstand the heavy deep-cycle use needed by most Japanese cars. Nissan, Mazda, and Honda tend to feature the latest in electronics and require a battery that can provide both slow, steady power and starting power.

This battery has 450 cold-cranking amps (CCA), which is enough to give you reliable starts, even in cold weather. Group 51 batteries are used in cars built for hot weather, too. This battery can work reliably in warmer climates without causing heating problems.

In our opinion, Optima YellowTop batteries are always a good choice. They have a solid reputation for quality and long life. They are resistant to vibration and shock, which makes them appropriate for cars and trucks used on rough roads or for off-road use. Optima batteries' exclusive Spiral Cell technology makes them perfect for seasonal use because they have a low-discharge rate. They will not run low when they are not charged for longer periods. This battery can even withstand starting when you forgot to turn down the stereo or turn off the heaters. Its reliable starting capability is one of the main reasons why it made this list.

• Good for all types of weather

• Lightweight

• SAE posts

• Good for dual-purpose

• Can withstand deep-cycle charging

• Does not have handles for carrying

3. EverStart Maxx Lead Acid Automotive Battery, Group Size 51R (12 Volt / 500 CCA)

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4. ACDelco Gold B24R AGM Group 51 Battery — Best SLI Battery

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ACDelco is a brand that has a long-standing reputation for reliability and long life. One of the best features of ACDelco batteries is that they have a durable case that protects them from vibration and shock. This makes them an excellent choice for trucks and other vehicles used off-road or on rough roads.

The battery design uses a calcium-alloy grid that resists corrosion and allows the battery to have better conductivity. This battery is an excellent starting-lighting-ignition (SLI) battery that will provide reliable starts on cold mornings. This model also has a strong handle that lies flat when not in use.

The battery is highly recommended for those who live in cold climates. ACDelco uses technology that improves conductivity across the grid. One of the downsides is that when you store this battery, the charge dissipates quickly. This is especially true when it is stored in temperatures only slightly below the average indoor temperature.

It is better to store this battery in a cool place, but not a place that gets below 30° Fahrenheit. This is one of the only drawbacks of this battery, but it should not be problematic in a vehicle that is driven frequently. This ACDelco is one of the less expensive batteries on the list and should do nicely for most cars and small trucks.

• Durable case

• Strong carrying handle

• Long Life

• Excellent conductivity

• Reliable starts on cold mornings

• Quickly discharges when stored above 70° Fahrenheit

• May need a charge before installation

5. Optima OPT8071-167 D51 YellowTop — Best Nissan Mazda 51 Battery

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The Optima YellowTop is one of the best batteries for both cold starts and Nissans loaded with electronics. It is vibration resistant and has a heavy-duty case that provides excellent protection. This battery has 450 cold-cranking amps and is excellent for cold climates. It has SAE posts and will fit most battery clamps easily.

Optima YellowTops offer a balance between starting ability and the ability to support electronics, such as winches, larger stereo systems, heated seats, and hydraulics. They are perfect for truck applications that rely on electronics to operate heavy equipment. Optima's technology creates a battery that will last for a long time and work reliably.

Optima batteries are always a good choice for cars and small trucks that require Group 51 batteries. If you are a person who needs to place your vehicle in long-term storage, or seasonal storage, this is the battery we would recommend.

This battery is also known for its ability to recharge quickly too. Optima YellowTop batteries are rated for over 300 charge/discharge cycles without any signs of failure. They are trustworthy and durable, and they are also spill-proof and maintenance-free. You can mount them in almost any position, except upside-down. This battery is an excellent choice for your Nissan or other Japanese cars.

• Excellent cold cranking amps

• Reserve capacity of 66 minutes

• Lightweight

• Long storage life

• Vibration resistant

• It requires two hands to lift and carry due to lack of handle.

• Not suitable for deep-cycle charging

6. Exide S51R Sprinter Classic 51R Battery — Best Honda 51R Battery

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We would recommend this battery for Honda cars, SUVs, and trucks that take a 51R battery. It is perfect when you need a heavy-duty battery made for the heavy loads placed on the battery by the Honda electronics systems.

Honda includes the Honda Sensing suite of safety technology that uses a complex system of cameras and computers to provide features like a blind-spot monitor and adaptive cruise control. Some models offer amenities like heated seats, wireless charging, and premium stereos with high-watt speakers. This places a heavy load on the battery and the durable. It is good for Hondas with a lot of electronics equipment and any other car with advanced technology.

One of the reasons we like this battery is that it outperforms many other brands in stop-and-go traffic. Exide tests their batteries under strenuous loads for long periods. This battery has one of the highest ratings for cold-cranking amps and reserve capacity.

The Exide battery uses SureLife Graphite Technology for a battery that performs like new for a long time. Customers report reliable starts at temperatures below zero degrees Fahrenheit. It might be noted that some customers in the extreme Southern United States have reported hesitation when starting on warmer days. This is an excellent battery, depending on where you live.

• Tested under strenuous conditions

• Good for heavy electronic loads

• Durable handle with grip

• Long reserve capacity

• Spill-proof

• Standard Lead-Acid (Non-AGM) battery

7. MegaVolt Lead Acid Flooded BCI 51R — Best Affordable Option

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Although many battery manufacturers are moving to AGM technology, some manufacturers still prefer to use lead-acid flooded batteries. Flooded batteries are less expensive than AGM, which is why many people still demand them. This battery is reinforced with a silver calcium alloy that provides efficient power. It has plenty of cold cranking amps and can be expected to start reliably in most situations.

For those who prefer lead-acid flooded batteries, this choice is an excellent option. It has plenty of power to provide reliable starts in cold climates. It is a long-lasting battery, but lead-acid batteries do not last as long as AGM batteries. One thing to note about this battery is that it is made in the USA. It also meets ISO 9001 and TS16949 certification requirements for quality in manufacturing.

• Durable flooded battery

• Can be recycled

• Maintenance-free

• Excellent seals

• ISO 9001 Certified and TS16949 Certified

• Carry strap feels cheap, use caution.

8. Duralast Gold 51R-DLG 500 CCA — Best for Cold Weather and Starting

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This Duralast battery has the most cold-cranking amps of any of the batteries on this list. It also has the highest reserve capacity. This is important if your alternator goes out, and you must run on battery power until you can get to a place where it can be repaired. It meets or exceeds the requirements that are common for vehicles requiring a 51R battery. This battery fits a long list of vehicles, including Lexus, Mercury, Mitsubishi, Porsche, Saab, and Toyota.

Duralast batteries are some of the toughest and longest-lasting on the market. They receive long lists of positive feedback from customers, including the ability to last long after the warranty has expired. One of the most common pieces of feedback is that when people replaced another battery with a Duralast, they experienced easier startups.

Duralast Gold is one of the best batteries for older vehicles that can be difficult to start. This battery has the power to get the most stubborn engines to start. It uses a paste instead of fluid for contact with the plates making the battery spill-proof and also provides better conductivity. We recommend this battery because of its design, reputation, and durable construction.

• Recommended for cold weather

• Long reserve life

• Durable and vibration resistant

• Maximum number of plates

• No handle for carrying

Buyer’s Guide and FAQ

Group 51r/51 battery

CHOOSE
THE BEST IN 2024

Before purchasing your next battery, it is important to understand terms meaning and how they affect battery performance.

The batteries on this list are the ones we consider to be the best ones that can be purchased online for those who have a vehicle that uses a 51 or 51R battery. The batteries on this list use different technologies, and they all have advantages and disadvantages. Here are a few of the questions that you might have about this battery group.

What is the best 51R battery?

When it comes to batteries, there is no overall best battery. Which one is best for you depends on the climate that you live in, the type of driving you do, and how many electronics your vehicle has on at the same time. Because shock and vibration can affect the performance of the battery, things like going off-road or on rough pavement can have an effect on which one is best. Some batteries discharge more quickly in warmer temperatures, making them less suitable for hot climates.

This is only the beginning of the list that can affect which battery is best for your purposes. Batteries from different manufacturers all have different strengths and weaknesses. The best source of information regarding your vehicle’s best battery can be found in the Owner’s Manual.

How to replace a Group 51R or 51 battery?

It’s very easy! You can use this video instruction:

Who makes the best 51R battery?

The conditions and type of driving that you do determine the battery characteristics that should be the most important for you. Increased electronics load and competition has resulted in improvements in batteries. As a result, many brands are an excellent choice. Some of them include ACDelco, Duracell, Optima, Duralast, Exide, and MegaVolt.

What does group 51R battery mean?

The 51R designation is the Battery Council International (BCI) number. This is a system of standardizing batteries so that they fit certain types of vehicles. The battery group number tells information about the physical dimensions of the battery, general power characteristics, technology used, and the location of the posts. This system assures consistency among the different types of batteries.

What are the dimensions and size of a 51R battery?

The dimensions of a group 51R battery are 9.3 x 5.0 x 8.75 inches, or 238 x 129 x 223 mm (Length x Width x Height). These batteries are taller and narrower than many of the common battery sizes. They are made for smaller cars that have tight spaces. Their tall size might make them unsuitable for engines that do not have ample space under the hood to accommodate their height.

What is the difference between a 51R and a 51 battery?

In BCI battery group designations, the R stands for “right” and refers to the positive battery terminal location. If the number has no letter designation, then it is assumed that the positive post is on the left. You can often substitute one designated with an R or without an R by turning it around in the battery holder if the terminal connectors are long enough to reach.

Group 51 Positive Red Terminal

Group 51R Positive Red Terminal

How long do group 51 batteries last?

Most of the group 51 batteries that we found had a warranty of 24-36 months. Some batteries in this group still use lead-acid flooded technology rather than AGM. These tend to have shorter lives, but some manufacturers still recommend this technology for their vehicles. The batteries on this list were chosen for their ability to last well beyond the warranty. How you drive and how well you treat your battery will affect how long it lasts. For instance, if you leave your lights on accidentally and phone charging when the car is not running often, it will shorten the battery’s life.

What is the cold cranking amps for my car battery replacement group BCI 51R?

The cold-cranking amps (CCA) of the battery is the battery’s ability to produce a short burst of power when starting the car. After this burst, the alternator will recharge the battery. Group 51R batteries have between 450 and 500 CCA, but some have less.

How many amp-hours is a group 51R battery?

Most group 51R batteries are between 36-45 ampere-hours. They typically have a reserve capacity of between 65-75 minutes.

What other size battery is close to 51R? Can I use a group 24F battery?

If you are unable to locate a 51R battery, the best replacement is a group 51. In some vehicles, you can successfully replace a group 51R with a group 24F. A group 51R battery is a common battery type in the US and Japan, but it is also taller, which means that a shorter battery might work. The main issue is that it is narrower and will not fit securely in wider battery holders. You can use this video instruction to put the 24F battery in your car instead of the 51R, but you should have a new battery tray:

What vehicles are compatible with a group 51R battery?

A group 51R is a common battery group size for U.S. and Japanese auto manufacturers. Some people also choose them for whole-house generators and as battery storage for solar panels. Here are some of the vehicle brands and types that we found use 51R batteries.

• Acura – 57 models
• Austin-Healy – 5 models
• Fiat – 20 models
• Ford – 1 model
• Honda – 397 models
• Infinity – 4 models
• Lexus – 3 models
• MG – 9 models
• Mazda – 44 models
• Mercury – 1 model
• Mitsubishi – 2 models
• Nissan/Datsun – 70 models
• Porsche – 10 models
• Renault – 41 models
• Saab – 21 models
• Toyota – 16 models
• Triumph – 4 models

As you can see from this list, the 51R battery is a common size for a wide range of vehicles. You should consult your Owner’s Manual to determine if a group 51R is recommended for your vehicle, even if it is listed here.

What amps is best to recharge a 51R battery?

Battery chargers list the batteries they are compatible with and should not be used with those not listed. Battery chargers come in a range of amperage sizes from about 0.75 amps to 60 amps. You should never exceed the maximum voltage and amperage of your battery. It is also important to choose a battery charger with a charge controller and a transformer, if needed.

How long does it take to charge a 51R car battery?

How long it takes to charge your car battery depends on the size of the charger that you get. For example, if you want to charge a 45-amp car battery with a 10-amp charger, it will take about five or six hours to recharge it from fully depleted. It will also depend on whether you use a rapid charger or trickle charger for maintenance purposes.

Where do you get a 51R battery?

A group 51 or 51R car battery can be found at many retail outlets and car parts stores. You can also order one conveniently using the links in this article and have it delivered right to your door.

Where do you buy a Duracell 51R car battery?

If you want to buy a Duracell 51R car battery, you can visit the official automotive Duracell website to find the right battery for your car. Then, you can use this form to find out information about dealers near you who carry them. You can also use the links in this guide as a way to order them quickly and conveniently.

What is the difference between and Autocraft battery 51R and Duralast 35-AGM?

The Autocraft 51R is 9 3/8L x 5 1/16W x 8 13/16H inches and the Duralast 35 AGM is 9 1/16L x 6 7/8Wx 8 7/8H inches. They are close but depending on the car, and they might not be interchangeable. A group 51R battery is about 10 pounds lighter than a group 35 battery, but they also have fewer cold-cranking amps. The smaller battery size might not be the best for colder climates.

How many months warranty are on a new 51R battery?

Most group 51R batteries have a 24 or 36-month warranty, but you can find some with longer ones. The biggest difference that determines the battery’s warranty is whether they use lead-acid flooded technology or absorbent glass mat.

Final Points to Consider

If you need a group 51 or 51R battery, you now have a few choices for batteries that are durable and long-lasting. The batteries in this group are from top manufacturers known for batteries that are suitable for a wide range of environments and driving conditions. They can handle the modern electronics of modern U.S. and Japanese cars.

The batteries on this list use different technologies, including older flooded battery types, AGM, and advanced spiral cell technology. AGM and spiral cells tend to have a longer life and better electrical properties, but flooded types tend to be cheaper. As cars include increasing electronic devices, the demand for more efficient batteries continues to increase in proportion. Dual-purpose batteries are becoming more important as the number of sensors and computers in cars that are always “on” places a long-term demand on the battery. This list is an excellent place to start for finding your group 51 or 51R replacement battery.

Eric Strong

Eric Strong works in the automotive repair industry more than 12 years. His work included repairing electrical systems in various vehicle systems. A hybrid electric car battery replacement experience expanded his understanding of automotive battery technology.