High voltage battery insight from Delphi Technologies
Delphi Technologies Academy EV content enhanced with high voltage battery insight.
Delphi Technologies has enhanced the electrified vehicle content on its training platform with the addition of a virtual insight into the workings of a high voltage battery.
Entitled ‘Inside a HV battery’ the short video provides viewers with an easy-to-follow understanding of the principles and components of the high voltage battery. This complements existing H/EV tutorials on the Delphi Technologies Academy learning platform – the company’s new online training resource. The HV battery introduction joins training materials on topics including instruction on how to lift an EV, information on protective equipment and modules that support the completion of popular IMI courses, such as the Hybrid Level 3 IMI programme – that covers everything other than working on a live battery or active system.
Phil Mitchell, Technical Services Manager, Delphi Technologies Aftermarket, said: “We recognised the increasingly urgent need for independent garages to have access to electric vehicle training a long time ago. The Delphi Technologies Academy and the introduction of online tutorials, such as the HV battery video, are part of our solution to help address the huge shortage in non-franchised garage personnel having the skills to work on electrified vehicles.
“The virtual content of the Delphi Technologies Academy perfectly complements our practical EV training, allowing us to offer a sought-after ‘blended learning approach’, but also enables users to significantly expand their knowledge of EVs in general. With the technology being so fresh, the content is suitable for those who are just starting out on their career right through to those who have spent 30 years in the industry.”
New Car Focus: BMW i4
By making its latest electric vehicle simpler, Rob Marshall finds that BMW has made the electric car better.
Regardless of whether you are a Bimmer liker, or hater, the company deserves credit for its stance on EVs. Back in 2008, BMW had embarked on ‘Projekt i’, an exercise that involved leasing 500 Battery Electric MINIs to selected North American punters and a further 24 to designated Londoners. This was not environmental greenwash. As BMW saw its moral responsibilities extending beyond the motorcar and into its ‘fuel’, it partnered with Norsk Hydro, the Norwegian hydroelectric firm that generated 28% of Germany’s total electricity supply at the time.
Sure enough, the fruits of the ‘Projekt’ included a continued relationship with hydroelectric power, which BMW now sources more locally and uses it in its factories. This is a crucial point, because EV’s environmental worth is undermined, if produced in a country, where fossil fuels provide most of the electricity, which is the situation in Germany, unlike the UK. ‘Projekt i’ also spawned the intriguing and promisingly different i3 and i8 models. Unfortunately, those high-voltage BMWs were built on expensive bespoke platforms and, despite being interesting and desirable, they are hardly mainstream. The new i4 five-door hatchback, or ‘Gran Coupé’ in BMW marketing parlance, is being launched alongside the iX SUV. Both vehicles are underpinned by the same basic Cluster Architecture (CLAR) BMW’s new i4 Battery Electric Vehicle (BEV) is a Gran Coupé (i.e. a five-door hatchback) with dimensions that are similar to those of a current production 3-series. Pictured is the rear-driven i4 eDrive40 platform that is shared with other petrol/diesel/hybrid BMWs, including the G20 3-series.
The BMW i4 eDrive40 is rear-driven, using a 335bhp (250KW) motor, and possesses a 366 miles range between charges and can dispatch 0-60mph in 5.6s. The i4 M50 has the honour of being the first all-electric BMW M car and is equipped with an additional electric motor on the front axle, giving all-wheel drive capability (albeit still with a rear drive bias) and a combined output of 536bhp (400KW), translating into a 0-60mph acceleration time of 3.9s and a 317 miles stated range.
The fifth generation eDrive drive unit comprises the electric motor, inverter and a single-speed transmission. BMW claims it has a 50% higher energy density than a current i3.
BMW claims that the electric drive motors boast a 93% efficiency rating, which helps to keep down the battery size and weight.
Addressing the critics…
The i4’s handsome but conservative looks hints at technical convention. Indeed, on the surface, there is little to surprise and delight: the battery pack is fixed to the floor pan, while the main motor/transmission/differential is mounted beneath the boot floor. Yet, looking closer reveals clever thinking to address common EV criticisms. While the precise battery cell technology is not revealed, BMW has made the batteries less bulky, championing a cell height of 110mm. It is also another manufacturer that realises how disproportionately heavy battery packs harm handling and efficiency. It has also strived to keep pre-assembly component distances as low as possible. BMW produces its prismatic cell modules in Dingolfing (Germany), the flexible assembly specifications of which vary according to model. The batteries are then transported to Munich. The i4 possesses four modules, containing 72 cells each and three 12-cell modules, giving a gross energy content of 83.9kWh. The battery warranty lasts for just under 100,000 miles, or eight years.
While it cannot do much about the locations in which the precious metals are situated, BMW has taken the human rights problems of cobalt mining into its own hands, by sourcing the rare element from mines in Australia, rather than the Democratic Republic of the Congo. The company has also strived to reduce the cobalt content within the battery packs, although as the ~5% cobalt (traditionally) accounts for ~95% of a traditional high voltage battery’s scrap value (lithium is relatively worthless), this might make it harder to justify recycling from an economics point of view. Even so, BMW claims a 90% recycling rate, compared to the EU legal limit of 50% by weight.
BMW i4 assembly takes place in Munich, on the same production lines as petrol/diesel/hybrid 3-series and M3 models.
The i4’s high-voltage battery pack is fitted to the underside by a fully-automated system.
Perhaps more importantly, BMW utilises electromagnetism to replace permanent magnets within the drive motors, avoiding the need for expensive and rare earth elements to be used in their production. This is a radical departure from convention, by making its EV less dependent on very rare and expensive elements. With the US considering the imposition of tariffs on neodymium magnet imports, BMW’s decision may be crucial to reduce the cost of EV production – although whether these savings will be passed to the customer, or not, is another question altogether.
Under the skin…
The voice-activated HVAC system possesses three zones. The cabin filter uses nano-fleece technology and more conventional activated carbon to enable ultra-fine dust and even certain micro-bacterial particles to be kept out of the cabin. A pre-conditioning function can be activated by the driver via the BMW smartphone app, prior to entering the car.
The basic thermal management (i.e. not just cooling but also heating) for the battery and associated hardware comprises three coolant circuits, interconnected by electric valves, all of which share a common expansion tank. This can, for example, allow heat from the drive motor to warm the battery pack. The new heat pump system uses 75% less energy than the current i3 and consists of a high-voltage refrigerant compressor, a pair of evaporators, a water-cooled condenser, and two 9KW heaters for extremely cold conditions. Surprisingly, the resultant energy savings can increase driving range by up to 30%. While the advantages offered by enhanced battery density, less weight and a more efficient drive unit benefit handling and acceleration, BMW has also considered that EVs tend to have feeble towing capacities. Yet, the i4 can tow up to 1,000 kgs.
Dependent on specification, up to 40 ADAS systems can feature, although they all work using camera, radar and/or ultrasonic sensors. Out of the six categories of automation, defined by the Society of Automotive Engineers, the i4’s systems achieve Level Two (i.e. ‘partial automation’), where both steering and speed are controlled simultaneously. While Distance Cruise Control is hardly novel, the i4’s system can also stop the car at red traffic light signals. While BMW says this feature is unique to the segment, it has not been confirmed if its availability is restricted only to the German market. The Route Monitoring function is another noteworthy feature, because it uses the satellite navigation system to select the appropriate speed for the selected route.
Summary: By normalising its new BEV, BMW has improved the electric vehicle in several important ways, especially by reducing its environmental impact at the manufacturing stage. The i4 will be available in the UK from November. Prices start at £51,905 for the i4 eDrive40 and commence at £63,905 for the i4 M50.
Compared with the i4 eDrive40, the i4 M50’s suspension differs by possessing adaptive M suspension dampers, an additional front strut brace, an increased track width (26mm front, 12mm rear), increased negative camber at the front axle and additional rear axle reinforcement. Both models boast self-levelling rear air springs.
Give replacement batteries a bright future
With battery sales predicted to remain buoyant throughout 2021, Rob Marshall provides an overview of relatively recent battery developments, while focussing on testing and maintenance advice.
Despite today’s 12 volt batteries inheriting the same basic lead-acid principles that were discovered over 160 years ago, numerous minor developments have occurred to increase their lifespans, boost charge acceptance, enhance output and be less maintenance intensive. Many of these changes have continued unnoticed by drivers and technicians alike. This tended not to have any significant consequences, until recently.
BATTERY TECH: AN UNNECESSARY COMPLICATION?
Technicians of all ages would have noticed the increasing prevalence of electronic equipment in cars, a trend that has little chance of slowing. While market forces have dictated ever more comfort and safety equipment, environmental pressures are also responsible for vehicle electronics becoming incredibly demanding and complex. The challenge for manufacturers is complying with strict carbon dioxide (CO2) emission limits. CO2, after all, is a gas that is linked directly to fuel consumption: the more fuel an engine burns, the more CO2 results. This is not the same for all gases that emanate from the tailpipe, an important consideration that even some engine tuning specialists are unaware.
As fuel consumption is affected by engine load, it is beneficial to reduce drag on the crankshaft and capture some of the energy that would have been wasted as heat via the friction brakes. This energy can then be redeployed to assist the engine during acceleration. Besides, stalling the engine deliberately, without shutting-down any comfort and safety systems, also aids fuel consumption. CO2, therefore, drops.
Advancing lead-acid battery technology has been crucial to transform such energy and emission saving systems from motor show concepts into realities. While the terminology differs slightly, the ‘traditional’ type of 12v battery powers mainly the starter, lights and ignition circuits, resulting in some battery brands referring to them as ‘SLI’ types. This standard…
…technology is enhanced as a cost-effective means to allow the carmaker to achieve its CO2 targets. The result is the Enhanced Flooded Battery (EFB), which retains the same basic internal construction but EFBs achieve longer life, superior charge acceptance, a 2-4 times superior ability to tolerate deep discharges and a 15-20% higher capacity. Inside, the main differences are a higher number of thinner plates, extra ingredients added to the lead paste material and a reduced electrolyte level. The mats in Advanced Glass Mat (AGM) 12v batteries absorb the liquid electrolyte and are pressed against the positive and negative plates. This deviation in construction reduces internal space further, so that the manufacturer can add more plates without increasing the plastic case’s physical size. AGM batteries are fitted to more sophisticated and expensive vehicles that possess stop-start functions (at the very least). Their advantages include a far higher lifespan, a 30-40% increase in capacity and an ability to withstand deep discharges that are 3-6 times superior to SLI designs.
It is worth noting that, while all of these batteries fit within the 12v category and share the same physical dimensions, the internal differences are what counts. Therefore, never downgrade the technology type, despite the batteries looking the same on first glance.
TEST AND CHARGE…
Batteries suffered during the reduced drive-cycles that resulted from last year’s lockdowns and tier restrictions – and will continue to do so. The leading cause of battery failure is exposure to prolonged periods of charge below 12.5 volts, which encourages internal sulphation that robs the battery of capacity. The lower the voltage, the faster the rate of denigration.
Ecobat advises that AGM and EFB batteries are designed to accept higher voltages from their smart alternators. Therefore, the energy needed to start the engine can be replenished within several minutes, instead of ~20 mins for a SLI battery being recharged by a conventional constant voltage (14.4v) alternator. Naturally, this means that AGM batteries can also accept a higher charge rate, when connected to a main- powered charger.
GS Yuasa agrees but adds that both automotive and motorcycle AGM batteries benefit from a higher recharge voltage, such as 14.7V – 14.8V, compared to 14.4v for SLIs. Yet, AGM batteries do not possess liquid electrolyte that can absorb and disperse heat. This means that AGMs are more sensitive to overcharging and this explains why they tend not to be installed within an engine bay but in an alternative location that is less exposed to heat from the engine and exhaust systems. Yet, should you discover an AGM battery beneath the bonnet, ensure that all of its protective shields and covers are intact. When using a smart charger, choose one that possesses AGM-compatible algorithms to ensure a slightly higher charge voltage and prevent overheating damage.
If a customer covers a low mileage, you might be asked for your recommendations on home charging. As it can take around 20 minutes, or approximately 10 miles, of driving to replace the energy used to start the engine, a sound means of identifying whether, or not, home charging is necessary is to see how many miles the vehicle covers between MOT tests. Ecobat suggests that a car covering fewer than 70-90 miles and more than 15- 20 journeys per week indicates a low mileage user. This means that the car is not being driven sufficiently long for the battery to be recharged. Should you be asked about where a smart charger should be connected, consult the car manufacturer’s handbook, or that of the smart charger. With AGM and EFB batteries especially, do not recommend old-style trickle chargers, which tend not to switch-off and risk overcharging.
Should your customer use the car for multiple short runs, Ecobat warns that you should suspect battery voltage walk- down. This is energy that is taken from the battery, which is not replenished fully, prior to the next engine restart. While you can recharge the battery in the workshop (ideally overnight), you may have to advise that the customer either drives the car for longer distances, or invests in a smart charger for DIY home charging. This not only gives them a degree of protection against a potential non-start situation but the exercise also prolongs battery life, by keeping its voltage above 12.5v.
Should a tested battery display a low voltage but refuses to accept charge for long, Ecobat advises that you check the warranty time scale, or advise the customer to do so, if it looks relatively new and you did not supply it. Ecobat is one such company that tests every battery returned under warranty. Note that ineffective charging and parasitic drains will discharge and damage the battery, so a technician is wise to check for these issues, using a DC clamp meter, to see if the car is demanding excessive current after its various ECUs have shut-down. If the fault exists within the car and not the battery, expect a battery warranty claim to be rejected.
Once the battery is charged fully, you should check its state- of-health. This is measured in amps and compare the resultant figure against the battery’s CCA rating, which should be displayed on its case. In most cases, CCA cannot be replenished by recharging, although some smart chargers possess desulphation modes, which may help to restore some CCA, caused by the battery suffering a short-term sub 12.5 volts drop in its state-of-charge.
Even the best quality batteries cannot tolerate poor storage conditions between manufacture and installation. Quality battery manufacturers advise factors on how to store batteries so that they are delivered to the technician in the best possible condition, before installation. However, some garages possess a battery stock either to use within the workshop, or to sell direct to the public. An appreciation of how batteries should be stored is useful, for which we are grateful to Varta especially for its recommendations.
While battery state-of-charge below 12.5 volts affects capacity negatively while fitted to the car, the same is true in storage. It is wise to develop a process to ensure that any stored batteries have their state-of-charge analysed periodically and…
…charged (but not overcharged) when appropriate. As self- discharge rates (and, therefore, battery ageing) increase with temperature, batteries are best stored in a cool atmosphere between 15 and 20 o C. The electrolyte can also freeze and crack the case but this risk is unlikely to pose a problem, provided that the optimum state-of-charge is maintained.
When in storage, keep the battery away from strong sunlight, not only because of increasing internal temperatures but also it risks UV degradation of the plastic case. The oldest stock should be used first, in a first-in, first-out system, and note the maximum storage time indicated on the battery. Take care during handling and, to prevent the possibility of short circuits, do not remove the terminals’ plastic protective caps until the battery is ensconced within the vehicle’s tray. Avoid any impacts, which might crack the casing, as well
as damaging the internal plates. Neither bare batteries, nor their pallets, should be stacked. Keep the battery clean, too. Moisture and dirt can accelerate discharge rates. Varta highlights that its representatives have an insight of the whole supply chain and can advise on the best process to suit your business, should you be unsure.
USEFUL BATTERY FINDER RESOURCES…
The following links are useful to identify suitable technically-compatible quality replacement batteries that match OEM specifications:
Crisis Management: Updating your battery knowledge
While a ‘dead’ battery may be a disaster to some car owners, technicians risk courting huge problems if they downgrade replacement technologies. As lockdown harmed many 12-volt batteries, Rob Marshall argues that now is the time to update your battery awareness, before it’s too late.
COVID-19 has and continues to touch our lives. As revealed in the AT special supplement during the summer, batteries are probably the most affected motorcar component of the enforced lockdown. Even if you have not replaced many batteries yet, most degradation that might have developed over lockdown will become apparent as the nights draw in and temperatures drop.
Banner told us that, while it experienced a surge in demand during the spring and summer months, it expects winter sales to be especially buoyant, especially as furlough schemes end and more people start travelling again for work. It reports that its manufacturing plant in Austria took steps during the summer to ensure that production output can meet projected winter demand. GS Yuasa also reassures the aftermarket that it has taken similar measures, after experiencing, what it calls, “a dramatic increase” in battery demand, since lockdown measures were eased.
HOW HAS LOCKDOWN BEEN A BATTERY KILLER?
The reasons why 12v batteries fail, when allowed to discharge gradually, are fairly complex but Yuasa supplies worthwhile reading on this topic: www.yuasa.co.uk/reducedusage. In summary, 12v batteries prefer being fully charged. Should their voltage drop below 12.5 volts, crystals build on the lead-based plate material (sulphation) that becomes either very hard, or impossible, to remove. The rate of severity depends on the rate of discharge and the length of time. The net result is a reduction of capacity.
Unfortunately, many car owners have not received very sound advice about maintaining batteries during lockdown, which has worsened the situation in some cases. It may be worth educating your customer about battery care, should future lockdowns be introduced. GS Yuasa told AT that simply starting the engine once a day will not save the battery; it can possibly accelerate deterioration. This is because the energy lost to start the engine may not be replenished. Therefore, should the vehicle be started once a day and the engine not run for long enough, the battery will become deeply discharged, risking permanent damage.
A further problem is that 12v lead-acid batteries prefer a gradual recharge rate. Yet, many car owners do not appreciate this and imagine that their car’s charging system will replenish the battery fully with the car sitting on their front drives with an idling engine for a quarter of an hour, or less. As sulphation builds, the battery’s internal resistance rises, making the charging system work harder for longer. This situation allows a sulphated battery to ‘trick’ the charging system into thinking that the battery is charged fully, when it is not.
Additionally, virtually all modern cars inflict parasitic drains, on top of the battery’s’ natural tendency to discharge naturally. The rate at which the car does so depends from vehicle- to-vehicle but components responsible range from ECUs, clocks, alarm and immobiliser systems. Faults can also develop that increase this drain, such as courtesy lights that do not extinguish, to alternator defects.
You may find that customers seek your advice on removing and recharging the battery. Providing that the owner is fortunate enough to have a private drive, (or, even better, a garage), then you can recommend that they buy a smart charger and connect the battery permanently to the mains, following the charger maker’s instructions, naturally.
Alternatively, and presuming that their DIY skills are up to the task (or else you can consider offering assistance), they can remove the battery from the car and charge it indoors. While you can advise them to check that the battery’s voltage does not dip below 12.5v and charge it as required, emphasise that any domestic charging must be carried out in a cool and well- ventilated area. As certain batteries can vent hydrogen and oxygen during charging, an enclosed airing cupboard is hardly an ideal location, unless your customer wishes to re-enact the Hindenburg disaster at the flick of a light switch…
When advising about chargers, you might also wish to consider if those in your workshop are suitable for the latest battery technologies. Many decades-old trickle-type chargers languish in DIY garages and professional workshops, which are designed for flooded lead-acid batteries. These apply a constant voltage and a variable current, which declines gradually as the battery reaches full charge. Yet, they do not turn off completely, which risks overcharging, damaging modern sealed batteries, especially. In addition, they do not guard against acid stratification, which is when the electrolyte’s acidity in the battery is stronger at the bottom of each cell and weaker at the top. Smart chargers apply different voltage levels to overcome this, as well as including other programmes to help reverse sulphation. If left plugged into the mains permanently, they possess a maintenance cycle to keep the battery between 95 and 100% charged but they switch off to avoid overcharging. Many smart chargers also have different algorithms to cater for the latest Advanced Glass Mat battery technologies.
As with any customer complaint, accurate diagnosis must be your priority. Establish, for example, if a non-start complaint is the fault of the battery, the vehicle’s charging system, or components that draw an excessive parasitic discharge. LKQ Euro Car Parts explained that flat batteries, caused by vehicles’ systems not shutting down correctly, are more obvious when they are not used every day, which explains the increase in flat batteries that occurred soon after lockdown.
Battery testing considers two main parameters: the state of charge is measured in volts but this does not tell you whether, or not, the battery can turn-over a cold engine. The State of Health is established in amps, a figure that is compared with the Cold Crank Amps (CCA) figure printed on the battery side.
EVOLVING BATTERY TECHS…
While battery technology has evolved, it seems that technician knowledge has not kept-up. This statement was proven last year, when ECOBAT found that fewer than one in ten technicians, of over 400 it questioned, did not know the meanings of SLI, EFB and AGM. Perhaps we should not be surprised. One battery supplier that we contacted did not know, either.
With low emission stop-start and later micro and mild hybrid technologies becoming ever more popular within the past decade, batteries have had to change internally to tolerate the greater number of starts and handle different discharge and charging demands. With very basic stop-star models, the traditional SLI (Starter Light Ignition) is replaced by an EFB (Enhanced Flooded Battery). As its name hints, the EFB remains of the same liquid electrolyte construction as SLI but with numerous changes to enhance charge acceptance. These include thinner but more numerous plates and additional elements used in its construction, such as carbon and lithium.
AGM (Advanced Glass Mat) batteries can also be called VRLA (Valve Regulated Lead Acid) and feature glass mats, which absorb the liquid electrolyte and are pressed tightly against the plates. The result is higher efficiency, a greater tolerance of deeper discharges and a typical 30-40% increase in CCA, compared to EFB and SLI designs. Yet, they are significantly more expensive than flooded types, which poses a hurdle for customers to accept.
Just as brake pads wear whenever the pedal is applied, batteries also wear every time they are used. As stop-start systems increase the number of required engine starts, the different battery technologies need longer lives. GS Yuasa told us that the difference is considerable: A SLI battery tolerates up to 50,000 starts, which jumps to 270,000 for EFB and 360,000 for a typical AGM.
This diagnostics intervention is crucial for long life of the new battery. The majority of cars that feature stop-start technology possess a battery monitoring system, which tends to feature a BMS (Battery Management System) sensor on the negative terminal. As the system adjusts its charging algorithms to compensate for battery degradation, until it has reached the end of its useful life, the software must be reset, after you have installed a new replacement. VARTA explains that, aside from potential battery damage through overcharging, various functions could cease to operate, if the diagnostic reset is overlooked. The equipment affected includes not only the stop-start function but also various electrical ancillaries, such as the electric windows and even folding roofs.
Aside from their online portals, battery companies can assist with a comprehensive selection of hardware, too. ECOBAT boasts its ‘ONE BOX’ kit www.ecobat.tech/ brands/onebox/, comprising a tester, smart charger and an EOBD-based programming tool. The company is also operating a free battery training, assessment and certification programme. It works by watching this video www.youtube.com/watch?v=EyAwPUAljWA&t=1s and taking this assessment https://ebtuk.typeform.com/to/S8AOWi. Presuming that you pass, you can download a choice of branded (Exide, Lucas, Numax, or VARTA) or non- branded certificates from ECOBAT’s main website: https://uk.ecobat.tech/brands/one-box/one-box-assessment. LKQ Euro Car Parts is also emphasising that diagnostic training is important, when tracing parasitic drains and interrogating battery monitoring systems in particular. The company told AT that it is working hard to communicate with its aftermarket customers about the range of battery training options available, through the Auto Education Academy training platform.
CHANGING CUSTOMER PERCEPTIONS…
More exotic materials, increasingly sophisticated battery construction and time-intensive replacement mean that you might face extra challenges from the customer. The days of replacing a battery for under £100 are fading fast and you may have to quote the facts from this article to avoid suspicions (or even blatant accusations) that you are profiteering. Obviously, their higher cost makes it even more important that you do not discard a serviceable battery in the first place through misdiagnosis. Even so, be wary of a number of pitfalls that your customer could suggest to reduce their expenditure.
The main temptation is downgrading the battery technology, so fitting an EFB, or SLI battery, to a vehicle designed for an AGM would be very poor practice. Banner Batteries advise this should be avoided at all costs and joins VARTA and GS Yuasa in stating that batteries should be replaced on a like-for-like basis. Yet, such manufacturers concur that you can upgrade technologies as an upsell. Downgrading, meanwhile, will result in premature battery failure, a main cause of which is damaged plates, through deep discharge and subsequent fast recovery, which flooded lead acid types are not designed to support. Using an SLI in an AGM application can damage it to such an extent that it can lose as much of 16% of its CCA (capacity) in the first week of use. Understandably, this risks the unsatisfied customer returning to you for another battery, and an explanation about why various other functions have ceased working. Battery supplier warranties will not cover damage caused by incorrect applications.
Another problem is some customers supplying, or requesting that you source, a second-hand AGM battery for you to fit. VARTA told AT that is does not recommend this approach, because the used part’s previous life and its condition are unknown. Additionally, the battery management system (BMS) would have configured itself to the old battery and could use an incorrect profile to charge the replacement used one. While it is possible that the BMS might learn the battery’s condition, this is not guaranteed and, even so, would not occur immediately. Regardless, the risks still remain: curtailed battery life, potential dashboard error messages and functions ceasing to work. Obviously, you cannot reset the BMS to any value other than that for a new battery.
Aside from having to overcome customers’ historic presumptions on battery replacement costs, battery and charging system development over the last decade especially has dictated that garages invest in extra training and hardware. It is worth your while. Provided that you have prepared appropriately, you can reassure customers that you are capable of replacing batteries on even the latest models, as well as helping to secure a profitable area of the market that is certain to grow.
12-volt battery technology
As far back as
1859, the lead acid battery has proven to be an integral component in almost
every type of automotive vehicle including hybrid and electric. Even though
hybrid and electric vehicles make use of lithium-ion and nickel-metal hydride
batteries to store energy and propel the vehicle, the reliable 12-volt battery
is still utilised to power the vehicle’s 12-volt electrical system.
Here, we take a look at 12-volt battery technology and the future strategies being explored with technical experts from Autodata.
Consisting of no moving parts whatsoever inside, the 12-volt lead acid battery encompasses six galvanic cells, individually capable of holding 2.1 volts. Each cell incorporates a positive lead dioxide coated plate and a negative lead plate, divided by a grid as well as an insulating material called a separator. The entire structure is encapsulated in a hard-plastic container filled with a liquid solution known as an electrolyte made up of sulphuric acid and water. After a charge greater than 2.1 volts is applied to each cell, a chemical reaction inside the battery is triggered, creating electrical energy ready for use.
invention of the lead acid battery, there has scarcely been any noteworthy
upgrades in design. That being said, in the mid-1970s the progression was made
to the “maintenance-free” or “sealed” lead acid battery.
Yet, calling the batteries sealed strictly isn’t accurate as, irrespective of
terminology, maintenance-free or sealed batteries still include safety vent
valves that release internal pressure in overcharging or cell failure
situations. Precisely for this reason, they are also referred to as “valve
regulated lead acid (VRLA)” batteries.
What makes the VRLA battery maintenance free – requiring no topping up with distilled water – is the chemical reaction that occurs when the oxygen formed on the positive plate is combined with the hydrogen given off by the negative plate. This synthesis between the two compounds formulates water that is recycled by the battery, thereby making it maintenance free.
So, without straying too far from the chemistry of the VRLA battery, thesame concept has advanced into the gel and absorbed glass mat (AGM) battery. Gel and AGM batteries are still categorised as sealed and valve regulated batteries; nonetheless, significant differences between the two remain. The gel battery’s acid is congealed with silica to form a thick liquid mass whereas the AGM electrolyte is saturated into a fibreglass mesh-like mat separator.
This innovative leap in technology comes with many advantages; both batteries are practically maintenance free, resistant to vibration, have no free-floating liquid that can leak and are safe to be situated in limited ventilation areas. However, because the AGM battery can deliver high demands in current capacity and discharges very slowly, it is the automotive industry’s preferred choice and frequently fitted to the stop-start generation of vehicles.
At this point,
it is worth noting that vehicles fitted with battery monitoring systems will
require recalibration every time the battery is renewed. Battery monitoring
systems provide precise information on the status of the battery while taking
into consideration the effects of battery aging. Values such as current and
battery data must be reset using diagnostic equipment. If this is neglected,
overcharging can occur which causes the battery to fail prematurely.
Caution is advised when using external battery chargers as VRLA batteries are intended to be charged at a low charge rate and at a slow pace. Intelligent battery chargers capable of automatically regulating the voltage and current should be used to prevent damage to the battery. If there is any doubt concerning compatibility and usage, follow the product manufacturer recommendations.
The automotive industry’s search for the next evolution in battery technology continues. The definitive objective is to invent a battery capable of storing large amounts of electrical energy while requiring a relatively short period of time to fully recharge. The following examples offer a quick snapshot into some of the new strategies and elements being explored:
Solid state batteries replace the electrolyte found in current batteries with a solid substance to enhance energy mass. Because operating temperatures are low, any risk of fire or explosion is reduced. These batteries are thought to have a longer lifespan and are also considered cheaper to produce than existing batteries.
batteries use silicon in lithium-ion batteries. In so doing, the charge
capacity is increased which results in a battery that lasts considerably longer
between recharge times. Silicon as a material is abundantly available, which also
makes this a very viable option.
Fluoride-ion battery technology claims to store up to ten times more energy when compared to current lithium-ion batteries. However, currently fluoride-ion batteries only work at high temperatures so this temperature limitation needs to be addressed before this can become a realistic solution.
12-volt battery’s matured age, there is still room for improvement and the
teachings of the past indicate battery perfection can be a slow and calculated
progression. Significant advances in future battery technology are unlikely to
be overnight and the industry could expect timing of these advances to run into
multiple years or even decades.
Autodata’s dedicated battery disconnection and reconnection module provides technicians with all the information they need to efficiently and successfully work with today’s batteries. Features include diagrams that show the locations and procedures for disconnecting batteries; instructions on preparing the battery for disconnection; and a list of electrical components that need to be reset after the battery has been reconnected.
Does a car ever enter the workshop where you can’t locate
the battery? Are you seeing some start-stop cars with the start-stop system not
working, but not certain why? Do you want to stay up-to-date with the latest
developments on battery technology? The VARTA Battery World could help provide
the answers to these questions.
The VARTA Battery World is an online library of How-To’s,
Tips & Tricks, and best practice for battery testing and replacement. With
easy to access step by step guides and videos, the VARTA Battery World is a
useful resource for any workshop carrying out battery replacements, is totally
free to access and there are no prerequisites to accessing any of the content.
With battery fitment getting more complex, installing a
replacement battery on a new vehicle can take well over an hour. This is due to
the increasing number of batteries being installed in difficult-to-reach
places, such as under the seats or behind panels inside the cabin rather than
beneath the bonnet. The number of steps to change a battery is therefore
increasing, as removing seats and panels takes time and often diagnostic
equipment is required for re-programming the battery to the Battery Management
System (BMS). An example of a complex battery changeover is an Audi Q7, which
has 28 steps to remove the old battery and install the new replacement battery,
and takes 72 minutes!
There are also multiple lead acid battery technologies; as well traditional, conventional flooded batteries, there are also Enhanced Flooded Batteries (EFB) and Absorbent Glass Mat (AGM) batteries and depending on the vehicle and whether it has a start-stop system or not will determine which technology to fit. The VARTA Battery World is here to help. It can be filtered by category, so if you want to find information specifically about start-stop vehicles and why an EFB or AGM is required, you can do so easily.
Alternatively you might want to access some information on battery testing and replacement, so you can apply a filter and access information on that topic.
Taking the fear out of start/stop battery replacement
ECOBAT Battery Technologies (EBT) says there are still many workshops that have yet to grasp Start-Stop battery technology and are losing out on revenue. Its research has found that nationally, 43% of workshops turn away start/stop battery replacement, due to an assumption that fitting them is complicated and the necessary equipment costly. It could also be the potential negative publicity to their incorrect fitment, seen through recent news stories concerning a prominent chain and the subsequent demand for compensation, leading workshops to believe it’s best to steer clear of them altogether.
The number of Start/Stop vehicles entering the workshop, all of which are fitted with either an AGM or EFB battery, is only going to continue to grow. Since 2016, virtually all petrol and diesel engines have the system as standard.
ALL YOU NEED IN ONE BOX
EBT has developed ONE BOX, providing workshops with all the equipment needed to test and install Start/Stop batteries, and access to this profit potential, which would typically be charged at more than £185 per installation.
With the ONE BOX package and a little training, EBT says workshops will find that fitting these batteries correctly is not a complicated process and allows them to provide a more professional service, improving customer satisfaction and reducing the risk of future warranty claims due to incorrect installation or use of an inappropriate battery.
The bundle includes a battery analyser to assess the condition of the existing battery, a NOCO charger and OBD lead to support the vehicle’s ECU/data storage during replacement and a battery validation tool to ensure the new AGM/EFB battery is assimilated into the battery management system. The package can be also be supported with signage and point- of-sale material to promote start/stop replacement capability.
ONE BOX, and its other products including VARTA®, Lucas and Numax brands, are available through its motor factor customers. If a workshop’s regular supplier does not work with EBT, they can contact EBT direct, who will then arrange for one of its existing customers to supply it along with any necessary training.
PHONE: 01743 218 500
An electric future?
Battery specialist ECOBAT Battery Technologies (EBT) will deliver a technical presentation within the Technical Training Hub in the show’s ‘Garage Quarter’, to give technicians a glimpse of the future by addressing the realities of the growth in lithium battery technology and the responsibilities faced by workshops as the global trend for electric vehicles continues. See Page 47 for Technical Talks schedule.
Back on its stand (H81), alongside the VARTA range, EBT will display the Lucas portfolio, as well as its own Numax offering, to demonstrate the depth and breadth of products in its substantial armoury.
Start/stop equipped vehicles, the continuing trend towards fully electric alternatives, environmental responsibilities and the wider opportunities outside of the traditional automotive sector are all points of interest that many visitors will want to discuss and for which EBT has many compelling solutions. We therefore look forward to welcoming visitors to both the technical presentation and our stand, to demonstrate how we can travel the road together and look forward with confidence to a bright future.”
“Automechanika again provides us with the ideal occasion to connect with our customers and end-users, to help them gain a clear understanding of the challenges – and accompanying opportunities – that the latest technical developments present,” explains the company’s Sales Director, Paul Payne.