Optima vs. Interstate, and the Advantage of AGM Batteries

OK, so you need a new battery. Just like with everything, every brand says that they’re the best, and usually list the exact same reasons for why. But when you’re looking at the battery market, Optima stands out as being often quite a bit more expensive than most other brands on the market, including Interstate, which to me represents the Old Guard of the battery industry.

So what separates Optima batteries from more traditional car batteries from brands like Interstate? Well, there is a reason why Optima made their name in motorsports, especially in marine and desert off-road circles, where Optima became THE battery to use, and in some circles, it’s rare to see someone running something else. That reason is their take on AGM (Absorbent Glass Mat) battery technology, for a long-lasting, durable, and maintenance-free battery.

Car Battery Construction and How They Work

Modern lead-acid batteries are typically made up of 6 cells, each providing 2.1 volts to make up 12.6 volts at full charge, which is what your car’s 12v electrical system is based around. Each cell is made up of an array of positively and negatively charged lead plates immersed in an electrolyte, which in this case is a mixture of sulfuric acid and distilled water.

Without going into too much detail here, the electrical energy is stored in chemical form, and can be discharged in an electrochemical process to transfer negative and positive electrons between the lead, and turning the sulfuric acid into lead sulfate, forming water in the process. When the sulfuric acid is all used up, the battery needs to be recharged. From there, charging the battery reverses this chemical process, and ideally reforms the sulfuric acid in its original quantities.

Acid Layering and Where AGM Batteries Come In

The shortcomings of the traditional lead-acid battery design come into play with the issue of layering, also referred to as stratification. If one of these batteries is subjected to low voltage voltage charge or drain, the sulfuric acid electrolyte can become poorly mixed with the water, leaving stratified layers of high and low concentration, with the sulfuric acid settling at the bottom, leaving nothing but water up at the top.

The result of this is sulfation, which is when lead sulfate crystallizes on the electrodes and blocks the conversion of lead sulfate back into the original lead, lead oxide, and sulfuric acid — meaning lower charge acceptance over time and due to the lower viable surface area on the cells, worse cold start performance.

With AGM batteries, that acid layering is no longer possible, as the electrolyte is suspended in the glass mat, bound in place with the electrode plates. This prevents degradation, makes the battery virtually spill-proof, higher charge acceptance, and lends itself to higher durability.

Optima’s Advantage

Optima batteries use an advanced form of AGM in sealed individual cells called Spiralcells, using 99.99% pure lead plates. Spiralcell and Pureflow technologies give Optima batteries more than 15 times the vibration resistance compared to traditional batteries and make them maintenance-free batteries that cannot be spilled without taking serious structural damage — and at that point, you probably have bigger problems on your hands.

These designs also allow Optima to pack high energy density into lighter weight packages, tying into their advantage in weight-sensitive applications, such as motorsports, off-roading, and marine vehicles. The high vibration resistance and lightweight make for a no-brainer for these applications where stepping up to lithium-ion batteries are either cost-prohibitive or do not provide the reserve capacity needed.

Interstate’s Advantage

Interstate does make AGM batteries as well. They are very high quality and usually come in at a lower cost per the same size battery. They are a popular OEM replacement for factory AGM batteries and actually act as an original supplier for many brands as well. Interstate also has slightly better warranty coverage for their batteries overall, and with service centers all over the country, you might have easier access to getting a replacement.

The difference is that since their emphasis is placed more on OEM replacement applications and therefore use a more traditional cell structure, they do not have the same durability or weight advantages of the Optima batteries.

So Which Brand Is Best for You?

It really is a matter of weighing cost against your use case and needed performance. Is this a daily driver or a work/tow vehicle that you need reliable performance from in AGM or even traditional lead-acid battery form? Interstate is a great choice. I run one in my daily driver right now, as I live close to a factory outlet, and they offer great prices with always excellent service.

If you subject your batteries to harsh conditions, especially ones with high heat and vibration, then the Optima might be better for you. The weight savings are usually an advantage in these high-performance applications as well, so these two aspects go hand in hand to make Optima the best pick of the two in those cases.

Comparison of the Different Optima Batteries:

Optima RedTop: The Red Top series is purpose-built for powerful cold starting in applications without heavy running electronic accessory needs — usually the best choice of the three for stock replacement in applications where extra durability and long life are key. These are especially helpful in cold climates and for diesels for Optima’s highest initial cranking power to be able to start reliably every time.

Optima YellowTop: These are what you could consider the high-endurance choice. Yellow Top are deep-cycle batteries, which means they excel in applications with high electrical load above what you would normally subject a stock vehicle to. This includes accessories such as winches, high power lighting, hydraulics, high power draw audio equipment, and fridges — especially in vehicles that might need to power these accessories without the engine running. These are also the top choice for racing vehicles without an alternator.

Optima BlueTop: BlueTop batteries in their light grey case are essentially identical to the YellowTop batteries in the fact that they are starting and deep-cycle capable, but with added threaded terminals on top in order to accommodate extra accessories that need to be run. These are specially made for use in marine and RV applications, for trolling motors, mobile audio and entertainment, and other equipment you might need to run on a boat or RV.

What Else Might I Need?

A good battery charger/maintainer is essential for people whose batteries might sit for extended periods of time or be used in applications without an alternator or other form of generator, like for boats with trolling motors or in RV or other recreational uses.

Optima recently released two excellent models to do just that. These aren’t just basic trickle chargers either; they automatically monitor and adjust the voltage applied when charging depending on the charge level and battery health. With this capability, they’re able to charge dead batteries that more basic chargers aren’t able to revive.

Optima Digital 400 Charger: A 4 amp output charger with LCD display to give you information on the battery’s health, current charge level, and charge rate. The 400 has a small footprint and has a built-in hook/stand combo for easy use where it won’t get in the way and allow for easy monitoring.

Optima Digital 1200 Charger: This is the big daddy, packing a whopping 12 amps of charging from the main clamps, and then 4 amps for auxiliary charging. The 1200 gives you more control over how you’re charging your battery as well, and Optima is so confident in how these will extend the life of your battery that they’ll add another year to your warranty if you buy one of their batteries and this charger together.

If you’re still not sure whether to choose OPTIMA vs. Interstate, take a look at the thousands of car battery reviews available at AT. You can see exactly what people are saying about the various car batteries available and research based on your specific vehicle.