The Best Group 78 Battery – Buyer’s Guide

A BCI Group 78 battery is a common battery for vehicles requiring a battery with terminals on the side. It is identical in size and specifications to a group 34 battery, only sometimes, the top terminals will not fit in the vehicle because of height limitations. If you have a car requiring a Group 78 battery replacement, this review will help you choose one that meets your needs and give you reliable performance.

Best Choice

Optima Batteries 8004-003 34/78 RedTop Starting Battery

The Best Group 78 Battery

This AGM battery has 800 cold-cranking amps. Its SpiralCell technology allows better contact between the electrolyte and lead components, which means more current, faster recharge, and a more powerful initial burst for starting.

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Quick Guide to Group 78 Batteries

Image	Product
Best Choice	Optima Batteries 8004-003 34/78 RedTop Starting Battery Cold Cranking Amps (CCA): 800, Reserve Capacity (RC): 100, Amp-Hours (AH): 50 Battery Group: 34/78 Type: AGM Warranty: 36 Best for Cold Starts Check Price	Check Price
Best Value	Delphi BU9078DT MaxStart AGM Battery, Dual Terminal Cold Cranking Amps (CCA): 775, Reserve Capacity (RC): 120, Amp-Hours (AH): 55 Battery Group: 78 Type: AGM Warranty: 36 Best Affordably Priced Check Price	Check Price
Best Choice	Odyssey 34/78-PC1500DT Automotive and LTV Battery Cold Cranking Amps (CCA): 850, Reserve Capacity (RC): 135, Amp-Hours (AH): 68 Battery Group: 34/78 Type: AGM Warranty: 48 Best for Fast Recharge Check Price	Check Price
Best Choice	Northstar NSB-AGM78 Automotive Battery Cold Cranking Amps (CCA): 880, Reserve Capacity (RC): 135, Amp-Hours (AH): 65 Battery Group: 78 Type: AGM Warranty: 48 Best for Critical Operations Check Price	Check Price
Best Value	ACDelco 78AGM Professional AGM Cold Cranking Amps (CCA): 740, Reserve Capacity (RC): 115, Amp-Hours (AH): 60 Battery Group: 78 Type: AGM Warranty: 36 Best Deep-Cycle Battery Check Price	Check Price
Best Choice	Optima Batteries 8014-045 D34/78 Dual Purpose Battery Cold Cranking Amps (CCA): 750, Reserve Capacity (RC): 120, Amp-Hours (AH): 55 Battery Group: 34/78 Type: AGM Warranty: 36 Best Dual-Purpose Battery Check Price	Check Price
Best Choice	Deka 9A78DT AGM Intimidator Battery Cold Cranking Amps (CCA): 775, Reserve Capacity (RC): 120, Amp-Hours (AH): 55 Battery Group: 34/78 Type: AGM Warranty: 24 Best for Fast Start Check Price	Check Price

Product Reviews

Here are our top picks for Group 78 batteries.

1. Optima 8004-003 RedTop Starting Battery — Best for Cold Starts

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Optima RedTop batteries are known for their superior starting ability in cold-weather. This battery has 800 cold-cranking amps and a powerful initial discharge burst. If you have a vehicle that you must start in snowstorms or when the weather is less than perfect, this one we would recommend.

Optima uses an exclusive SpiralCell technology that allows better contact between the electrolyte and lead components. More surface area means more current, faster recharge, and a more powerful initial burst for starting. It is not a deep-cycle battery and might not be the best choice if you have to operate heavy electronic loads, but if starting reliability is the most important feature you want, this is one that we would recommend.

• 800 cold-cranking amps

• SpiralCell technology

• Good for cold-weather starts

• Strong initial discharge for fast starts

• No carry handle

• Not recommended for heavy electronics

2. Delphi BU9078DT MaxStart AGM Battery — Best Affordably Priced

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This Delphi battery is one of the most affordably priced on the list, and it is perfect for some applications. For instance, the delivery of the cold-cranking amps of this battery is extended, which means it has a longer initial burst. This is the perfect solution for vehicles that are hesitant to start. It has 775 cold-cranking amps, a reserve capacity of 120 Minutes, and more than enough power to get the job done.

The battery has posts on both on the top and sides – the DT Stands for dual terminals. This gives you more options for mounting, but you must make sure you have enough room inside your vehicle to accommodate the extra posts. This is an excellent choice for reliable starts and situations where you want flexibility in the posts’ position.

• Affordably priced

• Good for vehicles that are difficult to start

• Has a carry handle

• Has both top and side posts

• Side and top posts might not work for all vehicles

• Best for starting rather than deep-cycle use

3. Odyssey 34/78-PCI 1500DT Automotive and LTV Battery — Best for Fast Recharge

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Odyssey is a brand that is known for reliability in many circumstances. It is exceptionally vibration resistant and designed to protect it from Impact and constant mechanical vibration. This is the brand used by many emergency services and in light transport military vehicles. It has 850 cold-cranking amps, and many users report anywhere between 3 and 10 years of service life. It is recommended for both starting and deep-cycle use.

Odyssey batteries are known for their dependability when starting under difficult circumstances is critical. They are extremely temperature tolerant and have operating temperatures from -40 — 113 degrees F. Another feature about Odyssey batteries that makes them a trusted brand is that they have fast recharge capabilities and can withstand fast charging at higher amperage. They are rated for over 400 charge/discharge cycles, even under less-than-optimal conditions. This battery is recommended for a wide range of vehicles, including high-performance cars, 4×4 and off-road vehicles, and classic cars.

• Withstands tough environmental conditions

• Wide operating temperature range

• Resistant to vibration and shocks

• Long battery life

• Dual-purpose battery

• Heavy weight

4. NorthStar NSB-AGM78 Automotive Battery — Best for Critical Operations

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NorthStar is one of the most widely recommended batteries for fire trucks, ambulances, service vehicles, and other applications where starting ability is critical. This battery has 1050 cranking amps, 880 cold-cranking amps, and a 134-minute reserve capacity. It is a Group 78 battery with front thread terminals.

NorthStar batteries are recommended for high-performance cars when battery reliability is critical. This battery has excellent starting capabilities, and it is also excellent for deep-cycle use. It is a flexible battery that balances starting ability and the ability to power heavy electronics. One thing that makes NorthStar batteries so reliable is that they insist on using high-grade lead plates with few impurities. This gives them a long life and allows them to perform just like new throughout their entire life cycle.

• Front terminal posts

• Reliable starting

• Long reserve capacity

• Trusted brand

• No carry handle

• Bulky, heavy weight

5. ACDelco 78AGM Professional Automotive Battery — Best Deep-Cycle Battery

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ACDelco is another brand that is known for improved performance and increased battery life. This one is recommended for deep-cycle use and has a built-in hydrometer to help you check battery health. It has an extremely durable case that is puncture-resistant in that it is designed to separate the battery components. This allows it to avoid overheating and extends the battery life, and increases the acid circulation. This battery has a spillproof design that prevents leakage, and it has excellent vibration resistance.

ACDelco is a brand that drivers have trusted for many decades. Their technology continues to improve, and they use state-of-the-art manufacturing techniques. This battery has a durable case that is puncture resistant and has a robust envelope separator for better acid circulation. More contact between the electrolyte and the plates means better conductivity and longer life. This superior battery technology is one of the reasons why ACDelco remains a top brand for many drivers.

• Excellent battery design

• Spillproof

• Suitable for heavy electronics use

• Long life

• Durable case

• Carry handle is long, making installation difficult for some

6. Optima OPT8014-045 YellowTop Dual Purpose — Best Dual-Purpose Battery

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Optima Yellow Top batteries have a balance between starting ability and the ability to withstand heavy electronics use. It is useful, especially for those who live in a cold climate. You can easily run features such as heated seats, more powerful stereos, and advanced safety features.

Optima batteries use superior technology to have a long life and resist frequent discharge/recharge cycles. They are known for a good recovery, even when you accidentally discharge them below recommended levels. If you accidentally forget to disconnect your cell phone when the vehicle is off, this battery will start anyway. This is one of the qualities for which Optima YellowTop batteries are known.

• Both SEO and GM post

• 120-minute reserve capacity

• Lightweight

• No carry handle

7. Deka Intimidator 9A78DT — Best for Fast Start

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Deka batteries are an excellent choice if you need both deep-cycle and starting capability. It is a reliable battery for cold weather and has excellent vibration resistance. It can handle the electronic loads of modern vehicles and has excellent deep-cycle discharging and recharging capabilities. One thing to note is that some users report that this battery can have poor self-discharge under storage conditions where it is not connected to a vehicle. Other than that, most users report an excellent experience with this battery.

Deka batteries are known as an excellent brand that works reliably in most conditions. They are made under tight manufacturing controls and seem to have good consistency from Battery to battery. Deka batteries are used in private vehicles, commercial, marine, and powersports applications.

• Good starting battery

• Leakproof design

• Good for starting and deep-cycle

• Dual terminal

• Vibration resistance

• Not good storage battery

Buyer's Guide and FAQ

group 78 battery

CHOOSE
THE BEST IN 2023

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

Now you have our top choices have the best BCI Group 78 batteries that are available. Each one on this list has its own advantages and disadvantages. The one that is right for you depends on your vehicle requirements and is recommended by your Owner’s Manual. Now, let’s explore some of the most common questions about Group 78 batteries.

What is the best 78 Group battery?

A Group 78 battery refers to a battery with certain size dimensions. A Group 78 and Group 34 Battery are identical in size, but a Group 78 battery has terminal posts on the side. There are some cars where the hood does not have enough height to accommodate top post batteries. In these cases, a Group 78 battery solves the problem. In some cars, you can use either a Group 34 or Group 78 battery without any problems.

Group 34 and Group 78 batteries have similar specifications in terms of cold-cranking amps, amp-hours, reserve capacity, and lifespan. Some Group 78 batteries use thick plate technology and are suitable for deep-cycle use and cars that use heavy electronics. Other Group 78 batteries use thin-plate technology and are better as an SLI battery. Some Group 78 batteries use a combination of these technologies and are appropriate for deep-cycle and starting applications. Groups 78 batteries average between 750 and 800 cold-cranking amps. They have an average reserve capacity of 110 to 134 minutes.

What are the size and dimensions of a Group 78 battery?

A Group 78 battery has dimensions of 6.9 X 7.9 X10.3-inches. It might be noted that it has terminals on the side, so the width dimensions will also include the post’s length. Post length can vary among different battery brands. It is important to know this information before choosing a battery. Ensure there is enough clearance around the sides of the batteries to accommodate the posts.

What is the difference between a Group 34, Group 75, and Group 78 battery?

Sometimes you will see a Group 34 and Group 78 battery listed together as 34/78 or 34-78. This is because both of them have identical dimensions. A Group 75 battery has the same width and height as a Group 34 and Group 78 battery, but they have a slightly shorter length. A Group 75 Battery is 9.1 x 7.1 x 7.3 inches. Group 75 and 78 batteries have terminal posts on the side, so this won’t add to the width dimensions.

Many people question whether you can substitute a Group 34, 78, and 75 Battery. This is a more complicated question regarding these battery groups than with other top-post-only comparisons. Group 78 and 75 batteries are used when the engine compartment is short in height and the hood comes close to the engine components. In this case, a top post battery, such as a Group 34, might not allow the hood to close. That is the main reason for using a Group 78 or 75 battery. If you decide to substitute a Group 78 or 75 battery for a Group 34 battery, you must make certain that there is nothing close to the sides of the battery that might get in the way of accommodating the side posts.

Another issue when exchanging these battery sizes is the size of the battery tray and battery holders. For a Group 34 and Group 78 battery, the same battery holder tray should accommodate either battery. A group 75 battery is shorter, and the main concern is making sure the fit is tight and that the battery will not slide around. Sometimes, this might require replacing the battery holder tray with one more suitable to the Group 75 battery, but other times the security needed can be accomplished by using a better battery hold-down or bracket set.

How long do Group 78 batteries last?

Most of the batteries in this review are warranty for it between 24 and 48 months. A majority of them are warrantied for 36 months, but this does not mean your battery will last long or will not. Many factors help determine the battery life that you will experience.

The batteries on this list use AGM, or absorbent glass mat technology. This technology is a drastic improvement over older flooded LED-acid batteries. They are more vibration resistant, spillproof, and maintenance-free. The design of the battery means that these batteries have better contact between the electrolyte and lead plates. This gives them more stable power, and they are more resistant to power drain when in storage and under some of the most common abuses that batteries undergo. Some of the batteries on this list have reported much longer lives than expected by users. If you want to stay sure that you get the longest life for your battery, here are a few things to avoid.

• If you store your battery, make sure that it is within the temperature range recommended by the manufacturer;
• Avoid discharging the battery completely by leaving the lights on or leaving electronics on charge overnight when the car is not running;
• If you drive in heavy stop-and-go traffic or have a vehicle with stop/top technology, make sure that you choose a battery designed for this use;
• Have your alternator checked regularly to make sure it is charging the battery;
• If you have an SLI battery, make sure that you do not discharge it to low levels frequently;
• When charging your battery, make sure to use the recommended charger and do not exceed the amperage recommended by the battery manufacturer;
• Although fast Chargers are available, a slow trickle charge over a longer period is typically better for most batteries;

How many amp-hours does a Group 78 battery hold?

Most Group 78 batteries are between 50 and 65 amp-hours.

How do you replace a Group 78 battery in a car?

Replacing a Group 78 battery in your car is an easy task on most vehicles. You only need a few simple tools like a crescent wrench or socket set, a wire brush, and a few shop rags. Before you begin, make sure that your engine is off and that your emergency brake is set. Lift the hood and use the holder to keep it up. Now, you are ready to proceed.

• Remove the terminal connectors. Loosen the nut that holds the battery terminal connector to the negative terminal. Remove the terminal connectors from the post. Now, do the same thing to the positive terminal. Removing the negative terminal first will help avoid sparks;
• Remove the battery hold-down brackets. Next, loosen the wingnuts or hex nuts to the battery bracket and remove it;
• Remove the old battery. If the old battery has a strap or carrying handle, make certain it is in good condition before using it to lift the old battery out of the battery tray. If not, carefully lift the battery from the bottom. Because of the potential of battery acid, it is suggested that you use gloves before attempting this method;
• Inspect the battery tray holder. Next, take a good look at the battery tray holder components, terminals, and wiring to ensure that everything is free from rust and in good working order. If anything needs to be replaced, you should do so at this time;
• Clean the tray holder and connectors. At this point, you should use the wire brush and a ride to remove any rust Ford corrosion buildup from the terminals, battery tray, and any of the components. Make sure to wipe everything off with a rag before proceeding;
• Place the new battery in the holder. Lift the battery and make sure it is seated flush with the bottom and does not move around in the battery tray;
• Secure the battery. Replace the battery holder four straps, and make sure that the battery is secure;
• Reconnect the battery. It is now time to reconnect the battery terminals in the same manner, starting with the negative terminal first;
• Start the car. Once everything is connected and secured, you may now start your vehicle to ensure that everything is working correctly.

How long does it take to recharge a Group 78 car battery?

The length of time it takes to recharge a Group 78 battery depends on how far down it is drained and the type of charger you use. You can choose from low amp trickle chargers or buy a fast charger with higher amps. The following table gives you an idea of how long it will take to charge a Group 78 using different charger types.

Final Word

Now, you have our picks for the Group 78 battery. Any of these choices are an excellent pick for most circumstance. NorthStar and Odyssey are some of the best for reliable cold starts. All of the batteries on this list are the best for their recommended conditions and have excellent reviews.

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. Read More…