Replacing batteries on stop-start vehicles

Fitting cars with Stop Start, Alternator Energy Management and Brake Energy Recuperation technology is one approach vehicle manufacturers have taken to reduce CO2 exhaust emissions. In fact one in seven cars on the UK’s roads now have a stop / start system – that’s around five million cars. To support these technologies and emissions savings, new battery technology needs to provide:

  • Extended operation in lower states of charge
  • Acceptance of current from brake regeneration
  • Greater lifecycle to support the vehicles electrical system when the vehicle is stopped and the alternator is not charging

Fitting like-for-like is vital

This is why batteries originally fitted to vehicles with stop start are made to perform to higher specifications than standard flooded batteries. For instance a Yuasa AGM battery has over 200% more cyclic durability than a conventional battery. For this reason, when you replace an original equipment battery with an aftermarket battery, it’s vital that you fit like-for-like. That means using the recommended AGM or EFB battery of equivalent size, when replacing the original equipment AGM or EFB battery.

When a conventional flooded battery is fitted to a Stop-Start vehicle, it will typically fail very quickly – perhaps within just four months. The resultant expense and inconvenience is sure to be remembered by your customer.

Even if the battery has obviously been replaced in the past, it’s definitely worth checking whether the original battery was an AGM/EFB type, particularly if the vehicle is registered after 2008. Clearly explaining to your customer the importance of fitting a battery of correct technology for the smooth running of their vehicle will help them understand why you’re recommending a different type of replacement battery.

Tools to help you find the correct replacement battery

So you know that batteries should be replaced like-for-like, but how do you identify the correct battery in the first place? The good news is that The Parts Alliance and Yuasa can help. The Parts Advisors at your local Parts Alliance branch use the industry leading parts catalogue. With just the vehicle registration or make/model, they can check whether the vehicle should have an AGM / EFB battery or standard flooded battery.

Alternatively, renowned battery manufacturer Yuasa have developed an Online Battery Lookup system. Simply enter the vehicle registration, make / model or VIN and you’re able to see which Yuasa batteries should be fitted to the vehicle. There’s detailed information about the battery itself, along with technical specifications, diagrams and the option of downloading a Technical Data Sheet. It even estimates how long it’ll take to fit the battery. This comprehensive tool is free, quick and simple to use.

To compliment the system, you can request a ‘USB Smart Button’ from Yuasa.  This saves you having to remember the website address, as one press of the Smart Button takes you straight to the Online Lookup system. It couldn’t be any easier to use.

Care when fitting

Whilst there shouldn’t be any dangers when fitting a battery, there are still a few risks to avoid, such as electric shocks and the emission of hazardous gases from the battery itself. Firstly it’s important to wear protective clothing, such as gloves and suitable eye protection, to minimise the risk to personal safety.  It goes without saying that you should never smoke near a battery or allow naked flames nearby.

One of the main dangers is short-circuiting the battery terminals. Tools or jewellery can generate enough heat to cause serious burns and in some cases, cause metal to melt and splash.

So remove any metal objects you’re wearing, such as watches, never place tools near the battery and remember to disconnect the battery before starting work. Batteries can emit hazardous hydrogen gasses, so they should always be charged in a well ventilated area.  When handling a battery, make sure the mains is switched off before disconnecting charging leads and that cables are handled so they don’t cause sparking.

Finally, once the battery has been changed, reset the battery management system (BMS). This will be done through the on-board diagnostics port. If you skip this step, the stop/start system might not work and the battery’s operational life could be shortened or system faults could develop.