Batteries are vital to our daily life even while we sleep. Batteries power mobile communications devices, land transport and mobility services, emergency power supplies, remote monitoring, support for renewable electricity, cordless power tools, off grid electricity, marine transport and recreation activities such as camping and boating. They are used by all sectors of the Australian economy including agriculture, mining, transport, services, and manufacturing.

Batteries provide flexible, convenient, and reliable energy supplies for portable, remote, and emergency uses.

Batteries are often characterised by their chemistry or the chemical mixture that it is the driver of the reaction to create energy. The main commercial types sold by ABIA members are:

• Lead acid
• Lithium iron phosphate
• Lithium-ion
• Nickel metal hydride

Each chemistry performs differently and within each chemistry type there can be different battery designs applied further impacting performance. In purchasing batteries, it is important to understand:

• Charging times
• How many life cycles, recharging cycles, in a battery
• Safey features – such as tolerance to overcharging and built in features
• Maintenance requirements
• Tolerance to extreme temperatures both hot and cold

Battery performance is highly variable depending on temperature, application and the quality of the product in which the battery is used.

Batteries can be tested for technical, safety and product performance.

Starting capability

The main purposes of starter batteries are to:

• Supply power to the starter and ignition system.
• Supply power to lights, radio etc when the engine is not running, or to supply power when the vehicle electrical load exceeds the capability of the vehicle charging system.
• Act as a stabilizer in the vehicle electrical system by absorbing voltage spikes caused by the system thereby providing important protection for sensitive components in the electrical system.

Starter batteries are intended to be maintained at a relatively high state of charge by the vehicle charging system. Starter batteries do not typically cope well in ‘cycling’ applications, that is those requiring steady power over long time periods. If used in this way, this can vastly reduce service life.

Deep Cycle Batteries

Deep Cycle batteries are designed to cycle between fully charged and various depths of discharge. They are less effective at providing high bursts of power for engine starting and are best used to support power needs where there is a long and steady discharge, for example, providing power for

• Accessories in recreational, marine, and industrial settings where their connection to the electricity network is not practical
• Electric vehicles such as golf carts, motorised mobility aids and floor sweepers

Temperature and battery performance

Batteries require proper installation and maintenance to ensure that they continue to perform as required and the service life of the battery is maximised.

One vital variable that is often overlooked when installing and maintaining a battery is the ambient temperature of its location. This is an important variable because the temperature has a significant effect on the chemical reactions that are occurring in the battery. And although it might be a suitable temperature at the time of installation, foresight, and management of extreme heat and cold can help prevent stress on the battery.

Many people believe that cold weather is what kills a battery but what is often disregarded is the effect that heat can have on a battery. In fact, it is heat that can cause the most damage to batteries, it isn’t until it becomes cold that the effects of that damage are evident.

In cars, this is becoming more prevalent due to the usable space in an engine bay continuing to be compacted to make way for more complex systems. This reduction in space reduces airflow and on hot days greatly accelerates the chemical reaction. This causes advanced Positive grid Corrosion of the internal cells, creating greater internal resistance, essentially reduces the battery’s serviceable life.

It is important to note that Positive Grid Corrosion is a natural part of the battery’s life and is factored into the design life of the battery. It is only when left in extreme heat that this is accelerated. In fact, batteries that are left in ambient temperature over 40°C can reduce its life by up to 50%.

So why do batteries fail in the winter? If we remember Positive Grid Corrosion creates greater internal resistance. In winter, the viscosity of the engine oils becomes thicker creating additional resistance that needs to be overcome when trying to crank the engine, any poor or dirty connection will also generate additional current draw from an already struggling battery. Combine this with a slower chemical reaction, with additional resistance, it makes it even more difficult for power to be delivered. Like heat when it gets hotter, as it gets colder, the reaction becomes less, at 10°C the reaction is slowed down by 50%, and at 0°C it is 25%.

Although the battery seems to be performing perfectly in the summer heat, it isn’t until winter that the damage becomes symptomatic. Think of it as an injury you sustained when you were young. It is fine through your prime years, but as you get older, it begins to resurface and become a problem.

To avoid damaging your battery in the summer, keep your car shaded as much as possible and ensure that you have a suitable and high-quality battery. Premium batteries, especially those with warranties of more than 3 years, go through a more stringent quality control process that selects only the purest materials to be included in the product. These batteries are more resistant and designed to withstand heat.

Unfortunately, if damage has been done to the battery, it can be challenging to overcome the problems indefinitely. However, you can help the battery by ensuring in winter the battery is protected from the elements as much as possible and that its CCA rating matches or exceeds that of the manufacturers recommended CCA rating of the vehicle. In addition, it is essential to get your battery tested before winter to evaluate whether it will be able to perform during the winter months.

There are a range of sources that provide information on how to use and charge your battery safely. These include:

• manufacturer information on how to operate the applicance and battery within safely
• safety data sheets that your battery retailer can supply to you

Using charging equipment that is recommended for your applicance and is suitable for your battery is critical. You should also check that your charging equipment meets Australian Standards under the Electricial Equipment Safety System.

For energy storage systems, the Clean Energy Council has a list of approved batteries that have been tested to meet electricity quality and safety standards.

Fire agencies publish advice and tips on preventing and minimising risks from fires. This is an example from NSW Fire and Rescue on battery and charging safety.

Factors to look for when buying a battery and evaluating lithium battery product quality

This list is a starting point for thinking about components which will impact battery safety and quality.  As batteries are pre-assembled it is difficult to assess these from looking at the battery. That’s why it’s important to ask your battery supplier about a batteries capability and to provide independent test certificates to determine the battery has been tested to UN38.3 for safe transport and other international safety test standards such as IEC 62133 and IEC 62619.

1. Temperature sensors. The temperature sensor monitors the battery temperature to prevent overheating, which can result in a battery fire. When connected to the battery management system, if the sensor detects overheating it can shut down the battery to minimise the risk of fire. Not all batteries will have temperature sensors or well connected sensors.
2. Battery Management System (the ‘smarts’ or electronics). Commonly known as the BMS, the system is primarily designed to protect the battery cells by checking for over and undercharging and thereby preventing damage. It can undertake a range of additional roles such as: shutting down the battery if there is a risk, e.g. overcharging, of the battery being damaged; communicating information with external monitoring systems; and checking for other system health issues, such as loose connections. There is no BMS standard and there can be a high variance between batteries in BMS capability and functions. It is always important to check whether the battery has a BMS and if so, what functions are included in the BMS. Monitoring overcharging is no good if there’s not also a shutdown function.
3. Battery cells – new versus second life cells. Lithium batteries sold in the Australian market may not contain all brand new cells. Examples are emerging of batteries which contain a mix of new and second life battery cells even in brand new batteries. Ask the product manufacturer or distributor whether the battery contains only new cells or a mix of new and second life.
4. Construction. There is no standard for lithium battery construction, that is the assembly of all the battery components into the finished product. This means that the construction quality can vary for features such as: insultation on terminals to prevent short circuits; the amount of filling to protect battery packs and cells from movement; and wire management, how the BMS is connected to the battery components.