Car Battery Size Guide
Having a car that won’t start is a real hassle – especially if you’re rushing, don’t have any jumper cables or an extra car to use.
When you bring your car to your workshop, are you even sure they are installing the right car battery for your car?
Car batteries come in as many as 17 different sizes with different configurations of positive terminals (right or left), smaller terminal heads and specifications. Not to mention, there are at least 30 different brands here in Malaysia!
As a rule of thumb, you will want to fit the car battery that meets your car manufacturer’s original specifications.
At Carput, we have worked with different car manufacturers and developed an intelligent car battery matcher to help our customers decide on which car batteries to choose from.
Our car battery matcher instantly filters out car battery sizes that will not fit on your car.
Underspec vs Overspec
The idea of car battery under-specification and over-specification has been around for a long time with mechanics and engineers having different opinions about it.
It’s obvious that installing a car battery with lower specifications than the manufacturer’s recommendations will result in a quick death for the battery, but what about a battery with a higher specification?
A battery with a higher amperage will actually only need more time to complete a full charge from the alternator, which means the alternator is working extra hard to get the battery full.
However, depending on the size of the car battery, we believe that the impact in installing a more powerful battery in your car is pretty minimal.
Regular vs Start-stop Cars
The new invention of start-stop cars came in the last decade or so – but what impact has it made in the car battery world?
What kind of car battery do we need when dealing with these cars? We first have to think about the role of a car battery in a car, which is to provide sufficient energy to start a car.
With a regular car, the car batteries are called to action once for every trip – every time you fire the ignition.
However, with start-stop cars (Perodua Myvi Advance) we are dealing with cars that are automatically shutting the ignition and firing it again at every stop.
A start-stop car kills its engine whenever the car comes to a complete stop and starts the engine again when the brake pedal is released. A start-stop car actually requires a higher-spec car battery because it needs the power to be able to start the car multiple times per trip.
A common example is with the older versions of Perodua Myvis with the newer, start-stop version. Regular Perodua Myvis are traditionally fitted with the NS40ZL size car batteries, but the ones with start-stop function actually have to use the M42 size.
The M42 battery is actually an enhanced flooded battery (EFB) and should not be confused with the NS40ZL battery which is a standard lead-acid battery.
The EFB technology brings an improved charge acceptance and greater cyclic durability when operating in a reduced state of charge, perfect for the start-stop Perodua Myvi.
A Brief Note on Lawn Mowers
We have been using lawnmowers since the late 1800s. All the initial lawnmowers were completely mechanical devices. Very soon, we saw gasoline-engine-based lawnmowers that made the job of lowing a garden very fast and easy.
These types of mowers are very popular even today as they are very powerful and allow you to mow thick and tall grass very easily. Then we have the main electric-powered lawn mowers.
They are small and easy to maneuver in small to medium-sized gardens. As a result, they became very popular in the market. But the limitation is you need to drag the cable or you can reach as far as the cable allows you.
The next important type is also electric but this time it is in the form of battery-powered mowers. These are cordless devices and you can use them anywhere you want. Their ridiculous cost makes them a niche product.
Types of Lawn Mowers
The basic type of lawn mower is a Reel Mower. It is a mechanical device that runs on our muscle power. We have to push the mower and when the wheels rotate, blades mounted on a cylinder cut the grass with a scissor-like action.
Next, we have rotary mowers that are powered by electricity, a battery, or a gas engine. Of the three power sources, gas-powered rotary lawn mowers are very common and popular, especially in the North American market.
You get both push-type as well as self-propelled models in gas-powered mowers. These types of mowers are very useful for large gardens, usually up to half an acre.
If you have a relatively small lawn, then corded electric lawn mowers are ideal. They are silent (comparatively), do not pollute, and are easy to maintain. Maneuverability is the main concern with corded-electric lawn mowers. In most cases, you have to stay within 150 to 200 feet distance from an electrical outlet.
An alternative to this is battery-powered cordless electric lawn mowers. They are very easy to maneuver as you don’t have to worry about the electric cord. Cordless Lawn Mowers are heavier than their corded counterparts.
Depending on the size of the battery, these models allow you to mow continuously anywhere between 45 minutes to 2 hours. But the cost of cordless lawnmowers is very high.
All the models we discussed till now are push-type or walk-behind mowers. But there is another type in the form of ride-on or riding mowers. As the name suggests, you can sit on the mower and ride it across the lawn to mow the grass.
If you have a very large lawn, over half an acre, then it makes sense to invest in a riding lawn mower. Usually, the ride-on mowers are gas-powered with rotary-type cutting mechanisms.
You often hear the term lawn tractor when you browse for riding lawnmowers. While ride-on lawn mowers just mow the lawn, riding lawn tractors can mow the grass and much more.
With the correct attachment, you can use a lawn tractor for mowing, dethatching, aerating, fertilizing, and even plowing snow.
Understanding Lawn Mower Batteries
As we mentioned in the previous section, gas-powered lawn mowers are very popular, be it the walk-behind type or the ride-on type. Earlier models came with a pull-string to start the gasoline engine.
Depending on the age of the mower, you could start the engine with a single pull in case of a relatively new and well-maintained mower. But as it ages, the performance of this starting mechanism starts to fail and you might need to pull more than a couple of times to crank the engine.
This is where lawn mowers with starter batteries come in handy. These batteries work similarly to our car SLI batteries as they help crank the gasoline engine of the mower.
With the push of a button or twist of a key, you can start the lawn mower and don’t have to worry about any pull strings.
Comparison between Lawn Mower Batteries and Car Batteries
The moment we say lawn mower batteries are useful for easily starting the mower’s engine, we immediately start comparing them with car starter batteries. They are similar in some aspects but there are a lot of differences as well.
Let us begin with the similarities. Car batteries are usually flooded lead-acid type or sometimes maintenance-free gel-type. It is very rare to see other types of batteries as car starter batteries.
Even lawn mower batteries are lead-acid batteries and they come in both flooded as well as gel types. But surprisingly, you can also find lithium batteries for lawn mowers.
As the majority of batteries in both cases are of type lead-acid, their working remains more or less the same. The advantages and problems you have with car batteries, you also have them with lawn mower batteries.
This includes low cost, a simple charging system, the life of the battery, etc.
Does this mean can we use a car battery in a lawn mower? No. this is where the differences kick in. First thing, car batteries are much bigger than lawn mower batteries, both in terms of physical dimensions as well as capacity.
The main difference is the starting current they can provide, which we usually represent as Cold Cranking Amps or CCA. As car engines are quite large, their batteries must provide a lot of amps to crank the engine.
So, you usually see CCA ratings of 500A or more in car batteries. But lawn mower engines are small. You don’t need such large currents. That’s why you will see CCA ratings in mower batteries in the range of 130 to 150A.
Important Specifications of Lawn Mower Batteries
Continuing the previous section’s discussion, let us see some important parameters and specifications of typical lawn mower batteries.
Type of Battery
As we mentioned before, you can find both lead-acid and lithium batteries for lawn mowers. In the case of lead-acid type, you again have flooded, AGM (Absorbent Glass Mat), and Gel types. Each type has its advantages and disadvantages.
Lithium batteries or Lithium Iron Phosphate to be specific, are also becoming quite popular with lawnmowers. The charging and protection methods (or lack thereof) are very different between lead-acid and lithium batteries.
Lead acid batteries are affordable, heavy, and robust to operate in all climatic conditions. But the problem is you have to take care of them and make sure they are fully charged all the time. Speaking of charging, the number of times you can charge and discharge a lead-acid battery is very less.
Lithium Batteries on the other hand are expensive and lightweight. Even though they support a good number of charge/discharge cycles, they need special circuitry in the form of a Battery Management System or BMS to protect the individual lithium cells from overcharging, deep discharging, etc.
Charging lead-acid and lithium batteries is very different. You can get chargers that support both these battery types but double-check the capabilities of the charger before using. Do not blindly use one type of charger on the other type of battery.
If the lawn mower has an alternator (which is usually the case with riding-type lawn mowers and lawn tractors), it can charge the battery once the engine is on. But for smaller mowers, this is usually not the case. You have to charge the battery externally.
Size and Other Physical Parameters
Physically, lawn mower batteries are smaller. In the next section Lawn Mower Battery Size Chart, we will see the dimensions of some popular types of lawn mower batteries.
Another important “physical” aspect of lawn mower batteries is the terminals and their position. Unlike car batteries, which usually have a pretty standard type of terminals, mower batteries have more than one type of terminal to connect the cables.
Also, the position of the terminals might be different between brands, manufacturers, and battery types. Usually, in a particular battery group, the type of terminals and their position (which is almost always on the top) will be common.
But we cannot say the same when you go to a different battery group.
Voltage
The reason why we are talking about battery voltage is in the early days of lawn mower batteries, we used to get them in 6V ratings as well. But it is safe to assume that most modern mower batteries that we get today are 12V batteries.
This applies to both lead-acid and lithium batteries. So, all the batteries we are going to discuss in the guide are 12V unless otherwise mentioned.
Capacity
The capacity of a starter battery is an interesting specification. It represents the amount of current in amps a fully-charged battery can deliver for 10 hours straight.
We usually see the battery capacity specification as Ampere Hour or Ah. Depending on the size of the battery, its capacity can range anywhere between 10Ah to 40Ah.
Cold Crank Amps (CCA)
This is one of the important specifications of a starter battery, be it for cars or lawn mowers. What does CCA mean? Cold Crank Amps or CCA represents the amount of cranking current (in amps) a fully-charged battery can deliver for a period of 30 seconds at a temperature of 0°F.
As the size of the gas engine in mowers is small, you don’t need a large cranking current to start the engine. Hence, you will see CCA ratings of mower batteries in the range of 100A to 300A. You can find batteries with CCA ratings more or less than this range. You have to check your lawn mower’s manual as it will usually recommend a specific CCA value.
Lawn Mower Battery Size Chart
An important thing to remember before purchasing a new mower battery is they are significantly smaller than car batteries and within lawn mower batteries we have several sizes.
A Battery Group categorizes the physical dimensions of the battery. All the batteries falling in a particular group have nearly identical shapes and sizes. If you are familiar with car and boat batteries, there are we have several battery groups.
Let us now see some popular lawn mower battery groups. The groups in this list are no way near the full possible types but these are pretty common with mowers.
The following table is a Lawn Mower Battery Size Chart consisting of the common battery groups.
How To Choose a Replacement Lawn Mower Battery?
The common thing between a gas-powered lawn mower and a car is they both have engines. But we take cars very frequently to school, work, shopping, or other commuting activities.
This is not the case with lawn mowers. We use them only when we need to mow the lawn or garden. So, for the most part of its life, a lawn mower usually sits in a garage or shed.
Here comes the problem. As we take our cars out for a spin on a regular basis, the level of discharge of the car’s starter battery won’t be that bad. But as lawn mowers are sitting idle most of the time, there is a good chance that the battery will discharge pretty quickly.
If you have an external charger, then you can extend the life of the lawn mower battery. But in case you don’t have a battery charger, then you will at a replacement in a short time.
Comparison between Lawn Mower Batteries and Car Batteries
The moment we say lawn mower batteries are useful for easily starting the mower’s engine, we immediately start comparing them with car starter batteries. They are similar in some aspects but there are a lot of differences as well.
Let us begin with the similarities. Car batteries are usually flooded lead-acid type or sometimes maintenance-free gel-type. It is very rare to see other types of batteries as car starter batteries.
Even lawn mower batteries are lead-acid batteries and they come in both flooded as well as gel types. But surprisingly, you can also find lithium batteries for lawn mowers.
As the majority of batteries in both cases are of type lead-acid, their working remains more or less the same. The advantages and problems you have with car batteries, you also have them with lawn mower batteries.
This includes low cost, a simple charging system, the life of the battery, etc.
Does this mean can we use a car battery in a lawn mower? No. this is where the differences kick in. First thing, car batteries are much bigger than lawn mower batteries, both in terms of physical dimensions as well as capacity.
The main difference is the starting current they can provide, which we usually represent as Cold Cranking Amps or CCA. As car engines are quite large, their batteries must provide a lot of amps to crank the engine.
So, you usually see CCA ratings of 500A or more in car batteries. But lawn mower engines are small. You don’t need such large currents. That’s why you will see CCA ratings in mower batteries in the range of 130 to 150A.
Important Specifications of Lawn Mower Batteries
Continuing the previous section’s discussion, let us see some important parameters and specifications of typical lawn mower batteries.
Type of Battery
As we mentioned before, you can find both lead-acid and lithium batteries for lawn mowers. In the case of lead-acid type, you again have flooded, AGM (Absorbent Glass Mat), and Gel types. Each type has its advantages and disadvantages.
Lithium batteries or Lithium Iron Phosphate to be specific, are also becoming quite popular with lawnmowers. The charging and protection methods (or lack thereof) are very different between lead-acid and lithium batteries.
Lead acid batteries are affordable, heavy, and robust to operate in all climatic conditions. But the problem is you have to take care of them and make sure they are fully charged all the time. Speaking of charging, the number of times you can charge and discharge a lead-acid battery is very less.
Lithium Batteries on the other hand are expensive and lightweight. Even though they support a good number of charge/discharge cycles, they need special circuitry in the form of a Battery Management System or BMS to protect the individual lithium cells from overcharging, deep discharging, etc.
Charging lead-acid and lithium batteries is very different. You can get chargers that support both these battery types but double-check the capabilities of the charger before using. Do not blindly use one type of charger on the other type of battery.
If the lawn mower has an alternator (which is usually the case with riding-type lawn mowers and lawn tractors), it can charge the battery once the engine is on. But for smaller mowers, this is usually not the case. You have to charge the battery externally.
Size and Other Physical Parameters
Physically, lawn mower batteries are smaller. In the next section Lawn Mower Battery Size Chart, we will see the dimensions of some popular types of lawn mower batteries.
Another important “physical” aspect of lawn mower batteries is the terminals and their position. Unlike car batteries, which usually have a pretty standard type of terminals, mower batteries have more than one type of terminal to connect the cables.
Also, the position of the terminals might be different between brands, manufacturers, and battery types. Usually, in a particular battery group, the type of terminals and their position (which is almost always on the top) will be common.
But we cannot say the same when you go to a different battery group.
Voltage
The reason why we are talking about battery voltage is in the early days of lawn mower batteries, we used to get them in 6V ratings as well. But it is safe to assume that most modern mower batteries that we get today are 12V batteries.
This applies to both lead-acid and lithium batteries. So, all the batteries we are going to discuss in the guide are 12V unless otherwise mentioned.
Capacity
The capacity of a starter battery is an interesting specification. It represents the amount of current in amps a fully-charged battery can deliver for 10 hours straight.
We usually see the battery capacity specification as Ampere Hour or Ah. Depending on the size of the battery, its capacity can range anywhere between 10Ah to 40Ah.
Cold Crank Amps (CCA)
This is one of the important specifications of a starter battery, be it for cars or lawn mowers. What does CCA mean? Cold Crank Amps or CCA represents the amount of cranking current (in amps) a fully-charged battery can deliver for a period of 30 seconds at a temperature of 0°F.
As the size of the gas engine in mowers is small, you don’t need a large cranking current to start the engine. Hence, you will see CCA ratings of mower batteries in the range of 100A to 300A. You can find batteries with CCA ratings more or less than this range. You have to check your lawn mower’s manual as it will usually recommend a specific CCA value.
Lawn Mower Battery Size Chart
An important thing to remember before purchasing a new mower battery is they are significantly smaller than car batteries and within lawn mower batteries we have several sizes.
A Battery Group categorizes the physical dimensions of the battery. All the batteries falling in a particular group have nearly identical shapes and sizes. If you are familiar with car and boat batteries, there are we have several battery groups.
Let us now see some popular lawn mower battery groups. The groups in this list are no way near the full possible types but these are pretty common with mowers.
The following table is a Lawn Mower Battery Size Chart consisting of the common battery groups.
How To Choose a Replacement Lawn Mower Battery?
The common thing between a gas-powered lawn mower and a car is they both have engines. But we take cars very frequently to school, work, shopping, or other commuting activities.
This is not the case with lawn mowers. We use them only when we need to mow the lawn or garden. So, for the most part of its life, a lawn mower usually sits in a garage or shed.
Here comes the problem. As we take our cars out for a spin on a regular basis, the level of discharge of the car’s starter battery won’t be that bad. But as lawn mowers are sitting idle most of the time, there is a good chance that the battery will discharge pretty quickly.
If you have an external charger, then you can extend the life of the lawn mower battery. But in case you don’t have a battery charger, then you will at a replacement in a short time.
Things to Consider for Lawn Mower Battery Replacement
The first and most important thing while choosing a new lawn mower battery is to check the physical dimensions of the battery. Lawn Mowers have a slot for the battery that fits only one type of battery.
When we say one type, we mean one size. The replacement battery must fit perfectly into that slot and it should be loose (and if it is tight, you can’t even fit the battery into the slot).
So, check the owner’s manual or maintenance guide of your lawn mower and look for battery specifications. If they mention the battery group, then you can simply browse for that particular group and purchase a replacement.
What if you can’t find the battery group information? We have to old school and measure the dimensions of your current battery. With this information, you can look up any lawn mower battery size chart and compare the dimensions with the common and popular battery groups in the list.
After the battery group size, the next important specification is the CCA rating of the battery. Once again, check the user manual if they specify the necessary CCA of the battery. If not, look at the label of the current battery and you might find the CCA ratings.
When shopping, you need to match the CCA values. It can be higher than the current value, but never lower. But if you opt for a higher CCA rating, then you have to spend more money.
Another important thing is the type of battery. We have lead acid and Lithium Iron Phosphate as the two base battery types. Further, in lead-acid, we have wet or flooded, AGM, and Gel types.
Always choose a replacement battery of the same type as your current battery. The compatibility between different battery types is, to put it in simple terms, highly questionable.
Online RV Battery Size Calculator
If you’re still not sure which battery is best suited for your RV, try out Renogy’s online Battery Size Calculator, a powerful and convenient tool for anyone looking for an efficient energy storage solution. This online calculator helps you determine the battery bank size that best fits your individual needs.
You just need to input simple information about your off-grid RV setup, like the type of your devices, daily watt-hours used, and your backup power requirements, and the calculator will display your required battery size and capacity.
Renogy’s online battery size calculator will give you a custom recommendation within seconds after submitting your selections.
The Battery Size Calculator will also give you an estimate of the cost and total kit price of all the components needed to set up your off-grid RV solar installation. This is incredibly useful if you want an accurate budget overview that doesn’t overwhelm you with technical calculations.
How Long Do RV Batteries Last?
Different types of RV batteries have different life cycles. In other words, the lifespan of your RV battery depends upon its type and quality.
RV deep cycle batteries are divided into two major categories:
2.Lead-Acid Based Batteries
These two major categories can be further divided into smaller classifications, for example, Lead- Acid batteries are divided into:
1.Flooded or Wet-Cell Lead-Acid Batteries
2.Absorbent Glass Mat AGM Lead-Acid Batteries
On the other hand, Lithium-based batteries, AKA Lithium-ion (Li-ion) batteries have many different types, including:
1.Lithium Iron Phosphate LFP LiFePO4
2.Lithium Nickel Cobalt Aluminium Oxide NCA LiNiCoAlO2
3.Lithium Cobalt Oxide LCO LiCoO2
4.Lithium Manganese Oxide LMO LiMn2O4
If you refer to the battery chart below, you will see that at the same size (Ah rating), longer lasting batteries like LiFePO4 are more expensive.
So how long does each type of RV battery last?
Flooded Lead-Acid Batteries are the most affordable batteries. However, they are also the shortest-lived RV batteries you could buy. In addition, Flooded batteries are also the most demanding in terms of maintenance as their electrolyte needs to be regularly topped off.
On average, Flooded or Wet-Cell Lead-Acid batteries can last for around 500 life cycles. Depending on how you use your RV, this translates to approximately 2-4 years of reliable use.
Second on our list are AGM and Gel Lead-Acid batteries. These batteries share many similar characteristics and lifespans. On average, AGM and Gel can support between 600 and 1200 cycles of use, depending on the battery type and quality. This translates to around 3-8 years of use.
Lastly, we have Lithium Iron Phosphate batteries. LiFePO4 batteries typically have a lifespan of over 3000 charge-discharge cycles. Sometimes they even go over 4000 cycles of use. This translates roughly to over 10 years of conscientious use. For more related information, you can read another article: How long do LiFePO4 batteries last?
Best Lithium Battery for RV. Renogy LiFePO4
There are few better choices than Renogy’s diverse selection of the best lithium batteries for RVs. campers, and other mobile homes. Our range of 12V Lithium Iron Phosphate batteries is designed and engineered for use in RVs, boats, and other mobile homes.
Renogy Lithium batteries for Rvs offer the best-in-class performance with features such as:
Durable IP65 Water and Dust Proof Protection
Smart Battery Management System
Auto-balancing Function for Battery Banks
Automatic Energy Saving Mode when not in use
Remote Monitoring Functionality
80% Depth of Discharge without Reducing Battery Lifespan
3-5 Year Product Warranty (REGO)
Here are some of our top-selling RV lithium batteries:
The 12V 100 Ah battery is a great replacement battery for RVs because of its high quality. It can store approximately 1.2 kWh of energy, which is enough for emergent backup power usage. With a compact size of 11.4 inch x 6.8 inch x 7.4 inch, the battery takes up to 15% space less on your RV compared to other types of battery.
This battery is a perfect substitute for deep-cycled lead-acid batteries with a standard BCI group size. Designed with built-in automotive-grade battery cells, the lithium battery delivers excellent performance even under the effect of various loads. And if you are looking for monitoring functions on a lithium battery, it is also your ideal option. It offers stable access to Bluetooth connections as its Bluetooth 5.0 technology enables faster and higher-quality data transmission.
Have you ever run into the trouble of your lithium batteries dying in freezing weather? If you have, you may learn the importance of working temperature and self-heating functions for a lithium-ion battery. Hence, if you live in a cold area, we highly recommend you have a look at this self-heating lithium iron phosphate battery. The heating function of the battery will be activated once the temperature falls below 41 °F and stop working when the internal temperature returns to 50 °F upward.
If what you need is more than a solar battery, please visit Renogy online store for a wider range of selections. Our product lines range from monocrystalline solar panels to wiring accessories.
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