Batteries. The Do's, And The Do Nots.

Modding a Subaru can be a very distracting way to pass the time, but not in a bad way. Saving up, looking forward to your next set of wheels, exhaust, or coilovers can easily make us overlook the maintenance side of things. This is something every owner and enthusiast needs to wrangle in because what good are mods if your Subaru doesn’t work?

With that being said, we need to take a closer look at the overall importance of your battery. A battery is something most car enthusiasts aren’t excited to buy because most of us will not buy a battery unless we are in an emergency. We need to go to our local auto parts store, Costco, or call for roadside assistance to get a replacement, and conventional batteries are $150+ for your average vehicle. Conventional batteries in your daily driver can last 4 to 5 years on average, but then they become weak. The internal cells can no longer maintain a charge, we’ve all been there. With daily drivers, batteries will last the longest because your vehicle is used every day, and your alternator will maintain a proper charge and voltage for the next startup. A battery becomes weak if you go prolonged periods of time without starting. A conventional battery can completely drain in a few weeks because other electronic accessories such as alarms, or sensors can put a drain on your battery when your vehicle is not in use.

 

WHY BATTERIES ARE SUBJECTED TO MORE WORK IN NEWER VEHICLES

As mentioned before, conventional batteries in newer vehicles have to work overtime to make sure all of the electronics are working properly in newer vehicles. In the newer WRX, you have a larger tablet-style high-definition screen that controls the infotainment system, or other vehicles may have heated and cooled seats, power windows, sunroof, satellite radio, backup cameras, crash sensors, all these things will put extra stress on a battery. Manufactures may have tried to mitigate the situation by installing high-voltage alternators. In your average Toyota Camry from the early 2000s, this was not really an issue, and batteries could last 5+ years because it didn’t have large screens, GPS, or every driver assist available. It had power windows, a vanilla sound system, and lack of excitement with that sandstone beige paint job. Newer vehicles will have a conventional battery, and some models will also have a smaller accessory battery that operates the electronics of the vehicle.

 

PERFORMANCE MODS RELY ON A GOOD BATTERY

Let’s say that you have a 2019 STI, and you have a built short block with an upgraded turbo, larger injectors, dual fuel pumps with a surge tank, a tune, with all the trimmings. Now on an average vehicle, you need to see 12.6 volts on your battery. Meaning if you had a voltmeter or went to your local auto parts store and they checked your battery, their voltmeter should see 12+ volts to determine if your battery is healthy. Anything below that then that means that things are getting weak. So here is how a weak battery can affect the performance of a modded vehicle:

• If you have more than one fuel pump, and your battery is weak, the second (or third fuel pump may not engage during full boost because your tune may have a voltage threshold that operates those pumps. Below the threshold puts you at risk of leaning out the motor.
• A weak battery will really mess with your tune because it takes data from MAP sensors, fuel pressure sensors, oil pressure sensors, and if you have a tuned failsafe in place, they may not work.
• Many tunes are based on the data collected from a wideband O2 sensor. If your battery is weak trying to work with the alternator, your wideband obviously will have mixed signals, and can give false readings.
• A weak battery puts premature wear on your alternator.

 

I NEED A NEW BATTERY. HOW ABOUT A LIGHTWEIGHT BATTERY?

Braille 11lb Battery

For example, this is the Braille Lightweight AGM Racing Battery. When compared to your conventional battery that can weigh 40+ lbs. on average, this particular battery weighs just over 11lbs. This is ideal for those of you who are looking to save weight without taking drastic measures such as removing interior parts or go full racecar by cutting things out of the car. A lightweight battery is a great way to save weight, but there are some caveats, and we’ll get to that. For now, here are some of the benefits:

• Weighs 11.5lbs / 5.2 KG.
• 5.8” in length, 3.4” in width, and 5.8” in height.
• Operates on 12 volts.
• 904 pulse cranking amps.
• 15-amp hour.
• 13.2 full amp charge

 

COOL. WHAT IS AN AGM BATTERY?

Most regular batteries are fluid-filled. They contain water, and battery acid. If you hook up the battery cables to the wrong terminals, then your battery blew up in your face with battery acid burning holes in your clothes and burning your face causing severe burns. You better have fast cat-like reflexes. AGM stands for absorbed glass mat. These are fiberglass mats inside of the battery that absorb the battery acid and electrolytes, and it allows for more internal lead plates. The internal fiber mats absorb road vibration more effectively. With regular car batteries, you will notice rectangular lids on top of the battery, these are designed to allow the user or mechanic to refill and replenish the battery with water. Now the electrolytes cause hydrogen and oxygen to escape these lids, which corrodes the battery tie-down, as well as any bare metal surface if you have cracks or holes on your battery tray. AGM batteries have a valve-like design that regulates how much hydrogen and oxygen can escape, eliminating the need to refill those battery cells with water.

 

WHAT IS CCA?

CCA stands for Cold Cranking Amps. This is how many amps the battery can deliver when starting your vehicle when it’s cold. You need more battery power because cold oil is thicker which generates more rotational mass at the crank. Basically, your engine needs an extra push to start when it’s cold. Therefore, every vehicle requires a battery that has a minimal cold cranking amp (CCA) rating, and that is why when shopping for a battery you will notice on top of the battery sticker, it will have the CCA rating. If it’s too low for your vehicle, it won’t work. The higher the CCA the larger the battery will be. Typically, auto parts stores will have direct replacements for make and model in the right size to suit your vehicle.

 

LITHIUM WITCHCRAFT

Lithium has been a game changer especially after that last few decades where we have seen an increase in lithium-ion batteries as cell phones have become an extension of ourselves. Lithium comes from brine and mineral resources so extracting it and making it into a battery is quite the process, and this is why lithium-ion batteries are so expensive. Lithium-ion batteries aside from cell phone usage, is used on laptops as well. It is rechargeable, and the service life is far beyond capable of what a pack of AAA batteries can do. This is why when today while shopping at your local Home Depot, many flashlights now use rechargeable lithium technology, as well as other battery-powered tools. Lithium also maintains a charge for much longer when compared to a conventional battery that weakens without use. It is also much lighter than conventional batteries.

Braille does make lithium racing batteries for our cars, and they are an expensive mod with batteries costing over $1k, but it will perform, and it will last.

 

THE CAVEATS OF LIGHTWEIGHT RACING BATTERIES

What can kill a car battery for good? That is letting the battery die completely over and over, to where a jumpstart, or a charger can no longer make the battery hold a charge. We’ve all done this before where we accidentally left a light on in the interior or left the headlights on when you got to work early in the morning as we rushed into our desks avoiding our supervisor. A battery can be jump-started, and the alternator will recharge the battery as the internal acids and electrolytes can make energy. But doing this a hand full of times hurts the battery, hurts your alternator, and can certainly hurt other electrical systems in your vehicle by shorting out your ECU by blowing up a capacitor. Because of these reasons, you must take extra measures to make sure your battery maintains a healthy charge when not in use.

Now lightweight batteries, and especially gel-filled batteries are more prone to damage the more you let them die. Lightweight batteries do not have the mass and size of a conventional battery to hold internal fluids and acids, and gel batteries can’t be re-filled so when both examples die, they die for good.

 

HAVE A RACECAR? OR JUST A SUNDAY DRIVER? YOU NEED TO KEEP THE BATTERY ON A TENDER

Battery tenders are a must-have for those of you who don’t drive your car often, but you also need to keep your battery alive. Whether if you have invested $150 on a regular battery, or a lot more on a lightweight battery, a tender should be on that battery. Now battery tenders are sold at your local auto parts stores, and you can find them anywhere online. These are relatively inexpensive, but make sure you get a decent one. Battery tenders maintain a charger until your battery is fully charged but won’t overcharge the battery. They are a great way to keep your battery healthy and running strong throughout the battery’s life expectancy.

 

BATTERY SAFTEY – IF YOU’RE A NEWB AND DON’T KNOW WHAT THE CABLES DO

This is very important to avoid setting your car on fire, among a myriad of other problems. Batteries are dangerous. Before we get into this you need to know how not to hurt yourself by not blowing your battery up. You have two battery cables in your car. You have (+), and this is the positive cable, then you have the (-), and this is your negative cable. Positive cables are usually marked in red, or have a red cable, and negative battery cables are the ground cable, and it is a black cable that bolts to the chassis of your car. It’s simple, hook the positive cable to the positive terminal on your battery, and the negative to the negative. Now even the positive battery terminal will have black cables, but another way to distinguish a positive battery cable is that the terminal will be larger, and bulkier. The positive cable is a series of cables as well where they all merge. You have a cable that connects to the alternator. You have a cable that connects to the starter, and a cable that connects to the fuse box. All of these will merge to the positive connection. The negative or ground battery cable is one wire, connecting to the metal chassis of your vehicle. What happens is you are wrenching on your car, and you have a long wrench that touches the two battery terminals at the same time? That tool will melt in a fiery lightning bolt hell within seconds. THIS IS WHY YOU MUST DISCONNECT THE NEGACTIVE TERMINAL WHEN WORKING ON YOUR CAR. If you change out your alternator, starter, removing the steering wheel by playing with airbag cables or changing out the car stereo, you need to disconnect the battery before you have hands, fingers, and arms fried to perfection.

 

AND THIS IS WHY YOU NEED YOUR BATTERY PROPERLY SECURED AND MOUNTED

Batteries are heavy and you just got a new battery at the auto store, and now you’re carrying it to your car which seems miles away. You get it in place, connect the terminals, but won’t take the extra few minutes to make sure your battery is strapped down because you ran out of energy. Any guesses of what can happen? Anyone? Bueller? Anyone? So, if the positive and negative battery posts contact your hood, then you have a lightning show under the hood. Some hoods have insulation while others may not. The problem is that when speed meets a pothole it can make your battery jump high enough to make your battery contact your hood. When this happens, it can also create other shorts in your electrical components such as the ECU, alternator, dash lights, or straight up start a fire. And the main reason why race cars have a battery shut-off switch within arm’s reach in the interior, as well as the exterior is that if the race car rolls, and stops upside down, sparks from the battery touching a damaged hood could ignite fuel. Because of these reasons, sanctioned racecars are required to have a battery box to thoroughly secure the battery.

Mele Design 900-Series Battery Mount Raw 2015-2021 Subaru WRX/STI

 

LIGHTWEIGHT BATTERY MOUNT DESIGNS

Mele Design has a great selection of battery box options designed to work with a variety of lightweight battery applications. If you invested the large amount of money to get yourself a lightweight battery, or a lithium battery, keep it locked down in your car.

 

Mele Design Battery Mount 900-Series Textured Black 2015-2021 Subaru WRX/STI

 

Mele Design Battery Mount – 600 Series Raw 2015-2021 Subaru WRX/STI

 

GrimmSpeed Lightweight Battery Mount Black 2008-2021 Subaru WRX/STI

 

 

FOR THOSE OF YOU WITH REGULAR BATTERIES, PLEASE SECURE IT

As mentioned, an unsecured battery can lead to catastrophic problems to your car, sanity, and your bank account. Luckily, we have several options that can be found HERE. Not only do these options secure your conventional battery, but they also improve the overall engine bay aesthetics. Need an idea? Here are some options:

 

PERRIN Battery Tie Down Red 2002-2024 Subaru WRX/STI

 

SubiSpeed Aluminum Battery Tie Down Red 2015-2021 Subaru WRX/STI

 

Cusco Battery Tie Down 2015-2021 Subaru WRX/STI

 

FINALLY, BE PREPARED FOR EMERGENCIES

As mentioned before, at some point we did something to kill the battery at work, or while shopping such as leaving an interior dome light on, headlights, or some sort of auxiliary accessory that will drain the battery. You should always keep jumper cables in your trunk or keep an emergency jumper on you in case no one is around to give you a jump.

Scosche PowerUp 300 Portable Car Jump Starter / Flashlight / USB Power Bank