Basic Bus Battery Care and Maintenance

Basic Bus Battery Care and Maintenance             

Batteries have been around for hundreds, if not thousands of years, with examples of a battery type device being found near Bagdad.  They have become part of our daily lives, in everything from watches and cellular phones, to houses and cars.  But as common as they have become, few of us understand how they work or how to maintain them properly.  Let’s “charge” on into some “positive” information about batteries. 

A battery is simply defined as an electrochemical device that stores and delivers energy. Energy is chemically stored in the battery and when the terminals of the battery are connected through a resistive load, electrical energy passes through the circuit.

Types Of Batteries

1. Lead acid batteries

Lead acid batteries are the most common type of car battery, which rely on a lead-acid chemical reaction to get things moving. Lead acid batteries fall into the “SLI” category, which stands for “starting, lighting, and ignition.” SLI batteries provide short bursts of energy to power your lights, accessories, and engine.  Once the battery jolts the engine to life, power for the car is supplied by the alternator. Most vehicles come with a generic SLI battery from the factory.

This category is further divided into flooded, gel and Absorbed Glass Mat. All three types work under the same concept: one lead plate and one lead oxide plate are submerged in an electrolyte solution of sulfuric acid that triggers a reaction between the two plates.  A combination of such two plates is called a cell, where the chemical energy is stored in the battery. A typical lead acid battery has six cells. Each cell can produce about 2-volts of energy. In most car batteries you have six cells, and therefore a 12-volt battery. The sulfuric acid will trigger a reaction on the lead dioxide plate, causing the plate to produce two things: ions and lead sulphate. The ions produced by the lead dioxide plate react to the adjacent plate to produce hydrogen and lead sulphate. The result is a chemical reaction that produces electrons. The electrons race around the plates and generate electricity. The electricity flows out of the battery terminals to start your engine and power the electrical devices like radio, interior lights, and headlights.

Lead acid batteries rely on a lead-acid chemical reaction.  What is interesting is that this chemical reaction is entirely reversible, which is why you can jumpstart your battery and continue to charge it throughout the duration of its life. By applying current to the battery at just the right voltage, lead and lead dioxide will form on the plates, and you can reuse your battery until it retires from old age and requires replacement.

While charging a lead acid battery, the battery generates oxygen and hydrogen gas, which can be explosive. Therefore, batteries are typically mounted under the hood, where they dissipate and do not become condensed. When installing a battery in the trunk, a firewall must be installed to protect the passengers. The battery box must also be vented to the exterior of the vehicle.

The newcomers to the automotive battery realm are lithium-ion batteries and NiMh batteries. These batteries are commonly used in rechargeable applications for cell phones and other portable devices. Compared to the old lead acid batteries, these two are very stable and hold a charge for a long period of time, with the ability to release that charge quickly.

2. Lithium-Ion batteries

Lithium-ion batteries are very similar to NiMh batteries below. Lithium batteries are the most efficient car battery type and hold a static charge for the longest, which explains their whopping price. These batteries are becoming more prevalent in high-performance applications, especially where performance requires the batteries to be as light as possible.

In fact, Porsche recently replaced the conventional lead acid batteries, which typically weigh around 40 pounds, for Lithium Ion, which weigh only about 13 pounds. Such an upgrade came with a replacement cost of $1700.

A downside is Lithium-Ion batteries are not ideal for use in very cold weather, as they can be damaged in temperatures below freezing. Another is their short lifespan.

If the voltage of a lithium-ion cell drops below a certain level, it’s ruined. Lithium-ion batteries age like the other types and they only last two to three years, even if they are sitting on a shelf unused. Most lithium-ion battery packs will not last until the five-year mark.

3. NiMh batteries

NiMh batteries charge fast, but they have a faster discharge rate when idle. These are the type of car battery used in hybrid vehicles.  NiMh batteries use hydrogen-absorbing alloy as the negative electrode, and nickel oxyhydroxides as the positive side.

How Batteries Are Classified

Batteries are grouped into 3 main classifications: Group size, cold cranking amps, and reserve capacity. 

Group Size

Battery Council Industry (BCI) specifies standard battery sizes and configurations by group size. This includes standard overall size – length, width, and height of the battery – and standard terminal type and position.

Cold Cranking Amps (CCA) This industry rating measures the power a battery has available to start a vehicle’s engine at zero degrees Fahrenheit. For a 12V SLI battery, BCI defines CCA as the amount of current (number of amperes) a lead-acid battery at zero degrees Fahrenheit can deliver for 30 seconds while maintaining at least 7.2 volts.

Reserve Capacity (RC) A battery’s RC represents the length of time a battery can maintain a vehicle’s electrical needs in the event of a charging system failure (alternator failure). BCI defines RC for a 12V SLI battery as the amount of time (in minutes) that a battery can deliver 25 amps at 80 degrees Fahrenheit while maintaining terminal voltage of at least 10.5 volts.

How Spot a Bad Battery

Making sure your car battery is charged properly is critical to maximizing its life. The most common signs that your car battery needs charging or must be replaced:

• One of the most obvious signs is the warning battery light illuminated on the dashboard.
• Headlights are dim. When the battery is weak, it does not have enough power to run your car’s electrical components.
• You hear a click, or nothing at all, when turning the engine.
• Engine cranks slowly when starting.
• You need to press on the gas pedal to start.
• No-starting: The car just refuses to start.

Battery Maintenance Tips

Lead acid batteries require more maintenance, but all batteries have needs. Lead acid batteries must be charged constantly to maintain that charge. Leaving a LA battery on the shelf for 6 months will degrade the battery, especially if it is in cold weather. You must protect your batteries from freezing. In severe cold weather a battery can freeze, which will short out the plates and the battery will no longer charge. When a battery freezes, the sides of the box will bulge.  Long-term storage or even a couple of days in frigid temperatures can weaken a batteries charge. A trickle charger can stabilize your battery's power. 

Charging – When storing a battery long term, you should consider a trickle or maintenance charger. These low-amp chargers keep the battery from discharging over time without boiling the electrolyte, which can ruin the battery. There is another side to that coin though. A dead flooded (this does not work for gel or AGM types) battery that won’t hold a charge can sometimes be “jump-started” by boiling the electrolyte with a heavy high-amperage charge. This is because over time and charge/discharge cycles, the electrolyte crystallizes (Sulfation) on the plates. Boiling the electrolyte can re-absorb those crystals, making the battery useful again. This does not work for batteries that have shorted cells. The process for reviving AGM batteries is a little more complex, involving multiple batteries chained together. AGM batteries need a better-quality charger than a standard flooded battery, Optima Batteries offers an AGM-specific charger that doubles as a conditioner for long-term storage. Otherwise, a good, constant potential, voltage-regulated charger with the following rates- Charge / Absorption / Equalize between 13.8 – 14.6 volts @ 77°F (25°C), Float / Standby between 13.4 – 13.6 volts @ 77°F (25°C).

Corrosion – Corrosion is a problem with all batteries, moisture, metal and electricity cause electrolysis, the same process at work inside the battery, but in an uncontrolled manner. That green fuzzy stuff on your battery terminals is bad. It is the by-product of electrolysis, which is like rust for lead. Preventing it is simple and there are some methods that work better than others. You can buy the felt pads and anti-corrosion spray work, but not for very long. The key here is keeping moisture out while promoting a solid connection to the cables. A little Vaseline on the terminals goes a long way to protect against corrosion. Another solution is liquid electrical tape, which creates an airtight seal, but it must be cut off before removing the battery cable.

Water Level – Flooded batteries require water to function, over time, the water level decreases. While many flooded batteries are labeled “maintenance free”, not all are. You should periodically check the water level in your battery. If the water is below the top of the water holes, add some distilled water. You must be careful, the water in the battery is highly-corrosive. AGM and Gel batteries do not require water maintenance. 

Cables and Terminals – The battery can only do its job when the connections are good. Corroded cables and terminals, loose fitting terminals, etc. limit the alternator’s ability to charge the battery and provide juice to the car. All terminals must fit tight, if you can wiggle it by hand, it’s not tight enough. You should be careful with side-post terminals, as you can strip the threads and break into the case, causing electrolyte to leak out.

If your bus is having electrical problems that you think might be from a neglected  battery, call our Service Department to schedule an appointment with our mobile service technician – Service Appointment.