If you are in the United States, the term “H7 battery” might not mean much to you. The same can be said about an “H8” battery. However, if you have a modern car in Europe, these battery ratings mean a lot more. These two batteries are meant for cars.
Did you ever wonder what having an H7 or an H8 battery means for your car? Or for your budget? Let’s talk about the differences and similarities between these two batteries.
What is an H7 battery?
An H7 battery is a car battery. The term “H7” relates to the width and height of the battery itself. These batteries are known for having the 175 mm widths, and 190 mm heights. You might also hear them called “L4” or “77L4” batteries.
H7 batteries have similar dimensions and power to 94R batteries. As a result, they are often used interchangeably without much issue. H7 batteries are most commonly used in European cars. They’re pretty rare stateside.
With that said, there are a lot of different high-end luxury vehicles that use these batteries. Some of the more common ones include Cadillacs, Rolls Royce, BMWs, Mercedes, and Bentleys. If it’s fancy, it might take an H7.
Both H7 and H8 batteries are DIN-standard battery labels. This means they are labeled by DIN, the German Industrial Standard code system. These codes are starting to be replaced by the European Type Number system.
Even so, both of these labels are still remarkably common. H7 and H8 batteries are two of the most commonly-mentioned batteries to still be sold using DIN codes.
What is an H8 battery?
An H8 battery is a car battery that has very similar dimensions to an H7 battery. Like the H7, H8 batteries are 175 mm wide and 190 mm tall. However, their length is a bit different from H7 batteries and their uses are slightly different.
The alternative battery type that is most similar to an H8 is a Group 49 battery. With that said, you might see H8 batteries labeled as “L5” or “88L5.” Like H7 batteries, H8 batteries are pretty rare to find in the United States.
Much like H7 batteries, these batteries are used for upscale luxury vehicles and light commercial vehicles that have a lot of electronics as part of their build. They’re pretty respected batteries, even on car show forums.
H7 vs H8 batteries
Now that you know the basics regarding each type of battery, it’s easy to see why people mix the two up. Let’s talk about the key differences that make each battery type unique.
1. Potential replacements
One of the major differences between these two battery types deals with the potential replacements that you have. If you can’t find an H7 battery, you can use a 94R battery without much issue. The battery capacity is similar and so is the structure of the battery.
On the other hand, traditional H8 batteries don’t really have an alternative. You can’t use a Group 49 battery instead of an H8. You need to have an H8 if your car requires an H8. Some companies started to shorten 49’s to the size of an H8, but that’s the exception to the rule.
The big difference between these two battery codes is their size. While their height and widths are the same, the lengths of the batteries are different. An H7 is 315 mm long, while an H8 is 345 mm long.
This means that you *usually* can’t use an H7 battery in a car that requires an H8. The battery just won’t fit. With that said, some companies shrank the size of their H8 batteries so they are compatible with H7 cars. This is good if you want to add more power to your machine.
These different lengths may seem fairly minor, but they can make all the difference when it comes to battery replacement. Simply put, choosing the wrong battery can result in a battery that can’t even be properly placed inside your car.
PRO TIP – Size is not the only thing that you need to worry about when you are trying to buy a new battery for your car. Before you check out, make sure that the terminal types and orientation of the batteries match what you need.
3. CCA rating
The cold-cranking ability rating of a battery relates to the battery’s ability to perform in cold weather. Both H7 and H8 batteries have a good CCA rating, but the H8 is slightly more efficient.
H8’s can have a cold-crank of 1,000 amps with a 140-amp reserve. H7s have a CCA rating of 850 amps, usually. So if you live in a cold area, an H8 battery is going to be a better buy.
If you are worried about a laggy cold crank start, the good news with both of these batteries is that you shouldn’t get too worried. They far exceed a typical car battery’s performance in colder weather.
Some batteries have higher CCA ratings than their standard. If you want to get a higher-performance battery, you can find out the CCA rating by reading the stats on the battery.
4. Reserve capacity
This term denotes how long a battery can last before the alternator charges it up. H8’s have a higher reserve capacity. With that said, both battery labels have a decent reserve capacity, so it’s not like your battery will die at an inconvenient time.
Switching to an H7 or H8 battery is often an upgrade on a standard car battery. You should expect the car to start up on the first try, no sputtering. You also should expect a fair level of durability regardless of the battery label you choose.
Among car fans, a major difference cited between the two batteries deals with power. H8 batteries are more powerful than H7 batteries—as a general rule anyway. If you want a high-powered battery, an H8 makes more sense.
Most luxury cars tend to have high power demands, so if you are looking to increase performance, then the H8 is going to be a better purchase. The same can be said if you are driving a commercial car.
Sometimes, you might want to upgrade your car’s battery, but it’s important to recognize that this is not always doable. Some cars will not be able to handle more power than what their recommended battery offers.
If you want to get an upgrade, talk to a mechanic before you buy that battery. It could save you a return trip to the garage.
6. Battery warranty length
Battery warranties are currently under a bit of a change, so this is a case where “your mileage may vary.” Traditionally, H8 car batteries come with a six-year warranty while H7 batteries are generally backed for three years.
However, in recent years, things have been changing. Nowadays, manufacturers are more open to warranties that are good for three years across the board. Whether this is due to economic needs or other factors remains to be seen.
This should go without saying, but modifications to any battery will usually void the warranty. The same can be said about using a battery that isn’t recommended for your car. When in doubt, read the warranty’s guidelines before you get a new battery side.
Like with all car purchases, price is going to be a factor. Unsurprisingly, there tend to be trends that are worth noting when it comes to the price of H7 and H8 batteries. Both of these batteries are considered to be luxury batteries in their own rights.
Due to the higher power, better CCA ratings, and higher RC ratings, H8 batteries take more effort and material to make. As a result, they also tend to be more expensive than their H7 counterparts.
With that said, this is not always the case. There are some H8 batteries that are cheaper than high-end H7 batteries. Even so, if you want to outfit a car with an H8 battery, you should prepare to pay more.
The main differences between H7 and H8 batteries are the size, power, and CCA ratings that they hold. These can impact the price you pay for them and well as the type of cars you can power with them.
When in doubt about the type of battery you want to use, ask a mechanic. They are there to help you find the right battery for your car.