Whether you live in a hot part of the country or are just going through a hot season, then you know what it’s like to have your car’s battery suddenly fail. You may have even replaced that battery fairly recently, but yet you’re still left without a charge. While there may be something amiss with your car’s alternator, there’s a good chance that the heat in your area is causing issues for your car’s battery.

This can be a difficult issue to detect at first. In some cases, you may notice your headlights and taillights diming in advance of your battery giving up the ghost. But your battery may also simply fail without any advance warning at all. If that’s the case, you may be stranded or actively looking for a new replacement battery. This time around, it will be worth your while to find a car battery suited to your local warm weather.

This guide will help you do that and more. Herein, I’ve reviewed 6 of the best car batteries for hot weather to make it easy for you to find a resilient replacement for your car. I’ve also taken some time to explain why car batteries are harmed by hot weather, as well as provide you with tips about how to keep your new battery in peak condition.


Preview

Product

Capacity/Amp Rating (CCA)

Battery Type

Check Price

Optima Batteries 8002-002 34 RedTop Starting...

Optima Batteries

8002-002 34

800

AGM

Odyssey 25-PC1400T Automotive and LTV Battery

Odyssey

25-PC1400T

900

LTV

Optima Batteries 8025-160 25 RedTop Starting...

Optima Batteries

8025-160 25 RedTop

720

AGM

Optima Batteries 8014-045 D34/78 YellowTop...

Optima Batteries

8014-045 D34/78

750

AGM

ACDelco 65AGMHR Professional AGM Automotive...

ACDelco

65AGMHR

775

AGM

Optima Batteries 8020-164 35 RedTop Starting...

Optima Batteries

8020-164 35

720

AGM


Why Do Car Batteries Fail in Hot Weather?

Mechanics agree that heat possesses a larger risk to your car's battery compared to cold weather, which most drivers associate with battery failure. But why does heat cause such problems for automotive batteries? For starters, most car batteries are known as “wet batteries,” meaning they use a mixture of water and acid to transfer electric charge internally. Heat can cause these liquids to evaporate, leading to poor conduction or outright unit failure.

Also, this same evaporation process can cause a battery’s internal cells to become damaged. This occurs when, due to evaporation, a battery’s internal conduction plates become exposed to air. This results in damage across those plates' surfaces, which in turn causes them to conduct less electricity (if any at all). While this can be resolved by "topping off" your battery with new liquids, your best option for fixing a heat-damaged battery is to simply seek a replacement.


Choosing a Quality Car Battery for Hot Weather

Battery Type

There are lots of different battery types on the market today, some of which may be more or less suited to your car’s needs in hot weather. A deep cycle battery, for example, is designed to last longer than a shallow-charging SLI battery, making them ideal for situations where your vehicle will need to rely on its battery more than usual. These batteries can be susceptible to heat, of course, especially when that heat comes in conjunction with your vehicle’s output heat.

Valve-Regulated Lead-Acid (VRLA) batteries, meanwhile, are the most common type you’ll see used in cars. These batteries are sealed in their entirety, meaning that they cannot be serviced by adding in new liquids. This sealed style makes them less likely to “leak” liquids while in use, though, so that kind of maintenance may not be necessary in the first place.

Absorption Glass Mat (AGM) batteries are also common, though they are technically a sub-type of VRLA batteries. AGM batteries produce strong, short bursts of electricity when activated. This allows them to remain more reliable in hot conditions, so long as its thin, internal fiberglass surface mat remains intact.

Wet or flooded batteries often a cheaper option for motorists looking for a quick replacement. While these may sound enticing for this reason, they are the most susceptible to "liquid" loss due to heat. They also have a shorter lifespan altogether, even under ideal conditions. The same can be said of lithium-ion batteries. While they aren't that susceptible to heat-related losses of functionality, they are not compatible with the majority of cars on the road today.

Vehicle Compatibility

As you might expect, you should always ensure that your chosen replacement battery is computable with your vehicle. To do this, you should check details such as the battery’s charging system, terminals, and battery group/size to ensure they match what your car needs. As you’ll see, some batteries are suited to RVs and motorcycles only. Alternatively, you can also check to see if your prospective battery has been tested and approved for use with your make and model.

Amperage/Reserve Capacity

When it comes to automotive batteries, “amp hours” is used as shorthand to communicate a battery’s reserve capacity. In other words, this specification can tell you how long that battery will last when used continuously without being recharged. This specification shouldn’t be confused with power capacity, though. That metric describes how much power the battery itself can hold in total.

Safe Operating Temperature

Be sure to double-check if your prospective battery lists a safe operating temperature range. This can help you quickly identify if it is suitable for use in warm weather environments.

Build Quality/Durable Construction

You should always be on the lookout for the most durable battery available, even beyond resilience to heat. Ideally, your chosen battery should be vibration- and shock-resistant so that it can maintain a stable current while your car drives over rough roads. Also, the best battery for your car will be able to resist exterior cracking and corrosion, especially in and around its terminals.

Price & Warranty

As with all car replacement parts, be sure to compare prices so that you know you are getting a good deal. While you may be paying a bit extra to get a heat-resistant battery, that price still shouldn’t be higher than the market average. That being said, any battery price should factor in a productive warranty. These can save you money on a future replacement battery if your new battery fails to live up to expectations.


6 Best Car Batteries for Hot Weather Reviewed

1. Optima Batteries 8002-002 34

Product Specifications

Nominal Voltage

12

Capacity/Amp Rating (CCA)

800

Battery Type

AGM

Reserve Capacity (Amp Hours)

50

Dimensions

10 x 6.9 x 7.8 inches

Warranty

3-years

If you only have time to consider one item in this collection, take some time to evaluate the best car battery for hot weather – the Optima Batteries 8002-002 34. As my top pick, I am proud to tell you that this reliable replacement battery features a polypropylene enclosure unlike anything else I’ve seen on the hot weather battery market. This case is up to 15x more resilient against vibrations than its next competitor, making it durable enough to withstand many years of active use.

At its core, this battery’s performance is also excellent in almost all vehicle makes and models. In fact, this unit is one of the premier batteries to utilize a SpiralCell design that allows it to reach 800 CCA and 50 Ah reliably. That cell design also gives this battery an enhanced shelf life without any risk of leaking. Speaking of shelf life, you'll also be able to keep a great amount of additional charge in this battery. Whether you have it hooked into your car or have it sitting on the shelf, it'll hold a full 100 minutes of charge.

At only around $240, the Optima Batteries 8002-002 34 is reasonably priced compared to its features and specifications. As such, you shouldn't hesitate to pick one up and keep it stored in your garage for the next time your car’s battery requires a hot weather replacement.

Pros

  • SpiralCell design provides reliable output and long shelf life
  • Extended reserve capacity of 100 minutes
  • Polypropylene enclosure is 15x more vibration-resistant

Cons

  • Does not ship in its original box

2. Odyssey 25-PC1400T

Product Specifications

Nominal Voltage

12

Capacity/Amp Rating (CCA)

900

Battery Type

LTV

Reserve Capacity (Amp Hours)

65

Dimensions

9.5 x 6.8 x 8.7 inches

Warranty

4-year

While there was some tight competition for the top spot on this list, the Odyssey 25-PC1400T ended up as my first runner up. That shouldn’t give you any doubts about this battery, though. In fact, if you check out its specifications, you’ll see why I’m such a fan. The Odyssey 25-PC1400T can output 900 CCA, as well as maintain a 65 amp hours of reserve capacity. It can also provide a whopping 1,400 amps of power during a 5-second start-up, making it one of the best in its class for a reliable ignition.

The Odyssey 25-PC1400T's construction is also a major highlight given that it can extend this unit's service life out to as many as 10 years. This can clearly be seen in this model's tin-plated brass terminals, which are both corrosion-resistant and highly conductive.

Along the same lines, this model’s pure virgin lead plates can withstand years of use due to their extra-wide surface area. Even this unit’s use of a self-regulating relief valve and robust internal cell connections ensure that it is always able to provide a reliable electric connection when you need it.

The Odyssey 25-PC1400T also comes standard with one of the best warranties in its class. As a result, you’ll be able to get at least 4 years out of this battery while still being able to exchange it for a replacement.

Pros

  • Tin-plated brass terminals are corrosion-resistant and highly conductive
  • Pure virgin lead plates optimized surface area conductivity
  • Higher-than-average reserve capacity and cold cranking amps

Cons

  • Price tends to be higher when purchased in store

3. Optima Batteries 8025-160 25 RedTop

Product Specifications

Nominal Voltage

12

Capacity/Amp Rating (CCA)

720

Battery Type

AGM

Reserve Capacity (Amp Hours)

90

Dimensions

9.3 x 6.8 x 7.6 inches

Warranty

3-year

Next up is the Optima Batteries 8025-160 25, which keeps with its brand’s high standard of performance by providing users with a great set of specifications. As the best battery for both hot and cold weather, this unit features a reserve capacity of up to 90 amp hours, which is more than enough to meet your multi-season needs.

It also provides a 720 CCA reliably, making it fully able to start up your engine in the dead of winter. Even this model's 0.003 internal resistance is remarkable and speaks to this unit’s overall strong internal conductivity.

Speaking of conductivity, Optima isn't afraid to reveal the secret behind this fantastic hot weather battery. They say that their secret involves the use of 99.99% pure lead plates, which can outperform regular flat-plate batteries in head to head electric output. I’d certainly believe that that’s the case, given that this unit can reach a full 910 CA when fully engaged.

The Optima Batteries 8025-160 25 practical resilience is also worth noting, not least because this unit can be mounted in almost any orientation. That’s because this unit features a leak-proof internal seal that ensures its internal water and acid never evaporate away. Better yet, this unit’s polypropylene enclosure ensures that corrosion and vibrations never get a chance to take this battery offline.

Pros

  • 99.99% pure lead plates outperform flat lead plates
  • Can be mounted in any position due to sealed enclosure
  • Low internal resistance maximizes conductivity

Cons

  • Manufacturer is hit and miss when it comes to honoring warranty

4. Optima Batteries 8014-045 D34/78

Product Specifications

Nominal Voltage

12

Capacity/Amp Rating (CCA)

750

Battery Type

AGM

Reserve Capacity (Amp Hours)

120

Dimensions

10 x 6.9 x 7.8 inches

Warranty

3-year

Though a few models in this collection fit the bill, I'd still say that the Optima Batteries 8014-045 D34 is the best dual-purpose battery for hot weather. In particular, I'd point to this unit's deep-cycle and core cranking power as evidence. While I'll admit that 750 CCA doesn’t sound like much, this battery easily makes up for it by also providing 120 hours of reserve capacity. In conjunction with this model’s spill-proof AGM design, these specs allow you to keep this battery on your shelf for many years, just in case.

Also, you’ll likely notice immediately that this model is within Optima’s YellowTop line of products. While this makes its polypropylene case a different color, it also means that this battery has been rated for up to twice as much use as their RedTop line of batteries. To that end, this particular model has been rated to last up to 300 recharge/discharge cycles. That’s a remarkable amount of resilience, even in the face of extra hot or cold weather.

I will say that the Optima Batteries 8014-045 D34 is a little heavier than most batteries in its class. While that can make installing it a little more challenging, you might still be pleased to know that it can be installed in any orientation. So, it definitely comes with its share of tradeoffs.

Pros

  • YellowTop product line lasts twice as long as standard models
  • Rated to last through 300+ recharge/discharge cycles
  • AGM design prevents spills caused by vibrations

Cons

  • Heavier than most batteries in its class

5. ACDelco 65AGMHR

Product Specifications

Nominal Voltage

12

Capacity/Amp Rating (CCA)

775

Battery Type

AGM

Reserve Capacity (Amp Hours)

80

Dimensions

11.8 x 7.5 x 7.4 inches

Warranty

3-year

ACDelco is likely another name you’re familiar with in the battery industry. When it comes to the best AGM battery for hot weather, their 65AGMHR is actually at the top of the chart. That’s because this model’s Absorbed Glass Mat design fully encloses the battery’s electrolytes in a fiberglass cell, thus preventing leaks seen in lessor AGM batteries. This construction, in turn, allows this battery to maintain a longer shelf life while also being safer to use in your own vehicle, regardless of the environmental conditions.

Meanwhile, the ACDelco 65AGMHR’s specification sheet is nothing to cough at. For example, this model’s cells can provide a 775 CCA as well as an impressive 960 CA when properly utilized. At the same time, this battery offers 80 minutes of reserve capacity, which is right around the current industry standard. These specifications combined allow this battery to quickly and reliably power a car with extra electronics onboard, including seat warmers and a stereo system, without running dry.

The ACDelco 65AGMHR is a fairly wise investment, as well. It comes standard with a 3-year warranty that many users say they've been able to file claims with. If you buy this battery online, you're also sure to get a good deal. That's because its popularity makes it cost far more when purchased at an auto parts store.

Pros

  • Extra durable enclosure prevents heat and cold incursions
  • No free-flowing electrolyte prevents spill risks
  • High maximum cranking amps in ideal weather conditions

Cons

  • Slightly lower-than-average reserve capacity

6. Optima Batteries 8020-164 35

Product Specifications

Nominal Voltage

12

Capacity/Amp Rating (CCA)

720

Battery Type

AGM

Reserve Capacity (Amp Hours)

90

Dimensions

9.3 x 6.8 x 7.6 inches

Warranty

3-year

Finally, we come to the Optima Batteries 8020-164 35. After some careful consideration, I’ve determined that this unit is the best hot weather car battery for the money that you’ll find on the market today.

Priced at just under $200, this battery’s price alone shows why it is so popular among bargain hunters. But as its spec sheet reveals, the Optima Batteries 8020-164 35 is anything but cheaply made. It can still attain 720 CCA and maintain a 90 amp hour reserve capacity, the latter of which is just above average.

Also, despite its modest price, this model’s RedTop architecture allows it to have one of the most reliable 5-second responses in its entire class. In fact, if necessary, this battery can output a full 910 CA spark during your car’s ignition sequence.

As a result, you can count on this battery to power through heat or cold to keep your car running. Of course, this model’s vibration-resistant and corrosion-resistant enclosure and terminals play a part in that resilience as well.

Pros

  • Affordably priced at under $200
  • RedTop architecture provides rapid 5-second start times, even in cold or hot weather
  • Enclosure and terminals are vibration-resistant and corrosion-resistant

Cons

  • Tend to die without warning

Indicators of a Failing Battery

There are numerous signs that your battery is rapidly losing its capacity to hold a charge. For example, you’ll have reason to believe that your battery is failing if your car is slow to start or fails to start up when the key is turned. Also, dim head/tail lights while driving can indicate imminent battery failure.

However, some signs of a failing battery require some inspections of the battery itself. For instance, if you notice any film or corrosion on your car’s battery, it may be leaking due to conditions under the hood. Also, if you find yourself jumping your car's battery more than once between replacements, either your alternator or your battery likely needs to be replaced or repaired.


Car Battery Maintenance & Care Tips During Hot Weather

The first (and perhaps most obvious) tip for keeping your car’s battery well-maintained during hot weather is…keep your car’s battery cool. Whenever possible, give your battery a fighting chance by parking in shady locations. Along the same lines, you should decrease the demand on your car's battery whenever possible. In other words, unplug in-vehicle electronics whenever possible to make the most of your battery's current charge.

When it comes to more active maintenance, you should always try to keep your battery (as well as its posts and terminals) as clean as possible. This process also allows you to notice leaks that may otherwise cause harm to your battery's service life. In all cases, it may simply be worth your while to keep a spare battery in your garage. This can save you a lot of hassle if you discover that the heat has gotten to your current battery, despite your efforts.


People Also Ask (FAQs)

What shortens a car battery’s life?

Lots of factors can play into a battery’s service life. For example, driving habits can cause a battery to last a shorter amount of time, especially if said car’s battery is being used to power in-vehicle electronics often. Also, a car’s age can impact the efficiency with which it utilizes its battery, causing it to draw more electricity or potentially even overcharge the battery. Environmental conditions can harm a battery as well, with extreme cold and hot weather being the biggest risk factors for a failed car battery.

What is the best type of car battery for hot weather?

When it comes to picking out a battery for a hot weather environment, the type is less important than individual key specifications. For example, a battery with a sizable reserve capacity can be a major lifesaver. This is true in cases where your alternator fails, requiring you to drive on your remaining battery power until you can get it repair (liking for only a few hours in total). That all being said, liquid-based batteries are always at a greater risk for evaporation (and thus failure) in hot weather environments.

How much heat can a car battery handle?

Typically, a car’s battery can handle up to 140° F of heat before it begins to perform sub-optimally. This can occur cumulatively or suddenly, such as when a built-in cooling fan fails. At those temperatures, liquids inside the battery become more likely to evaporate. While these batteries are not likely to explode due to head, all efforts should still be made to avoid extreme heat conditions with your vehicle.

What is the best car battery brand?

There are numerous worthwhile car battery brands on the market today, many of which you can find in brick-and-mortar shops as well as on online retailers. These brands include Optima, AC Delco, and Odyssey. They can provide you the best performance in warm weather without burning a hole in your wallet.


Conclusion

When summer rolls around this year, you shouldn't need to sweat it out, worrying about whether your car's battery will die suddenly. You shouldn't have to worry, that is, if you pick up one of the great hot weather car batteries that I’ve reviewed above. Each will ensure that your car remains running as expected, regardless of how much heat and humidity the peak of summer brings to your area.

But before you go, I want to make one final recommendation about the best overall battery for hot weather use. To that end, if you’re in a hurry to find a useful replacement, be sure to pick up an Optima Batteries 8002-002 34. This battery has a solid standard of performance in all weather conditions thanks to its polypropylene case. It also has a 100 minute reserve capacity, which is more than enough to get you to safety in case of a sudden alternator failure.