12V lead-acid batteries are about to withdraw from the market?

“Sure, automotive 12V lead-acid batteries are about to withdraw from the market. Europe has issued a decree that after 2030, all new automobiles will now not use lead-acid batteries, which poses an important problem for OEMs to seek out different options. Though this may occasionally appear to be a frightening activity, it may well additionally carry large alternatives to not solely eradicate batteries which might be dangerous to the setting, but additionally to scale back automobile weight and enhance general effectivity.

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Sure, automotive 12V lead-acid batteries are about to withdraw from the market. Europe has issued a decree that after 2030, all new automobiles will now not use lead-acid batteries, which poses an important problem for OEMs to seek out different options. Though this may occasionally appear to be a frightening activity, it may well additionally carry large alternatives to not solely eradicate batteries which might be dangerous to the setting, but additionally to scale back automobile weight and enhance general effectivity.

The 12V battery and energy provide community (PDN) is a worldwide normal that helps a whole lot of hundreds, together with some hundreds which might be intently associated to security. Subsequently, the answer should be revolutionary and strong. The high-density, high-power, and high-efficiency energy modules used to attach high-voltage, 48V and 12V PDNs can present options with the very best flexibility and scalability for this upcoming problem.

When contemplating potential options, OEMs should think about a number of essential components: enhance energy to assist new options with higher efficiency, enhance effectivity to increase driving vary and optimize thermal administration, scale back carbon dioxide, optimize cable routing, scale back wire harness weight, and Meet EMI necessities. These are among the variables on this advanced equation.

There are two major choices for fixing this equation. Changing the 12V lead-acid battery with a 12V lithium ion battery is an choice. Though it does barely scale back weight, it should retain the decades-old custom of 12V PDN and won't produce different benefits. Another choice is to assist 12V PDN powered by 400V or 800V major battery in electrical automobiles and hybrid/plug-in hybrid automobiles. The latter choice has many benefits, however each choices are worthy of additional exploration.

Use 12V lithium ion battery

Merely changing the 12V lead-acid battery with a 12V lithium-ion battery can certainly save about 55% of the load, however it has a excessive price impression. A 12V lithium-ion battery requires a battery administration system (BMS) to manage charging and preserve the battery absolutely operational throughout the whole life cycle of the automobile. That is how Tesla and Hyundai are growing.

As well as, a big DC-DC converter (with voltage and present regulation traits) from excessive voltage to 12V is required to cost the 12V lithium-ion battery and energy {the electrical} load. However this is not going to add any benefit. What it provides is simply the load, the complexity of the general structure of the automobile, and the system price, and it'll additionally scale back the general reliability of the automobile. In distinction, eliminating the 12V battery can't solely scale back the load of the automobile by 13kg, but additionally enhance the cargo area by 2.4%.

Conventional 12V PDN is inefficient

Sustaining a 12V bodily battery means sustaining an inefficient PDN with pointless redundancy. In a typical automotive 12V PDN, all 12V hundreds related to the 12V bus have an inside pre-regulator that may convert a large enter voltage vary (normally from 6V to 16V) to 5V, 3.3V or decrease. From a worldwide system perspective, whether or not it's an electrical automobile, a hybrid automobile, or a plug-in hybrid automobile, there's a sequence regulator redundancy. A DC-DC converter from excessive voltage to 12V can stabilize the 12V bus (excessive effectivity), and the pre-regulator can present the suitable inside voltage for every load (Determine 1).

This conventional structure originated within the period when automobiles have been geared up with alternators. The alternator is a delicate 12V PDN that requires voltage regulation to cost the battery, preserve the radio working throughout start-up occasions, or preserve the automobile’s incandescent headlights correctly brightness. OEM producers have creatively bypassed the 12V energy limitation. In recent times, they've designed two 12V batteries, a 24V battery for energy steering, and a number of other DC-DC converters in between.

Determine 1: Typical E/E utilized by xEV, utilizing a 12V battery with a redundant voltage regulator. The excessive voltage to 12V DC-DC can stabilize the 12V output and cost the 12V battery. Every 12V load within the automobile has a pre-regulator to offer the right voltage required for the load to work. Determine 1: The scales of those two robotic platforms are fairly totally different, however their energy provide networks have loads in widespread. The modular strategy helps to finish the preliminary design with a excessive diploma of flexibility, and normally speeds the supply of subsequent energy system designs.

Change the 12V battery with a dummy battery

A greater option to clear up this drawback is to fully rethink the automotive PDN: abolish the 12V bodily battery and exchange it with the 12V “digital” battery in the principle battery of the electrical automobile (Determine 2). Each electrical automobile has a major battery, so it's meaningless to hold further vitality storage gadgets. The best automobile structure is to make use of a high-voltage battery to energy the ability system and all auxiliary hundreds. Vicor high-density bus converter module expertise can understand this scheme, it virtualizes the low-voltage battery (48 or 12V) straight from the high-voltage battery (400 or 800V).

Determine 2: The optimized E/E structure can eradicate the 12V bodily battery. Use Vicor BCM bus converter expertise to transform excessive voltage batteries to create digital 12V batteries.

Vicor BCM® bus converter adopts zero voltage, zero present switching (ZVS/ZCS) expertise, and its working frequency is increased than that of typical converters, so its response velocity is quicker than that of bodily batteries. For instance, the BCM6135 is totally different from the standard ZVS/ZCS resonant converter. The working frequency is 1.2MHz. The BCM operates at a narrowband frequency (Determine 3). The excessive frequency operation of BCM can present quick response to modifications in load present and a low impedance path from enter to output. The mix of mounted ratio conversion, bidirectional operation, quick transient response (greater than 8MA per second) and low impedance path might help BCM make the excessive voltage battery appear to be a 48V battery, which we name “transformation.” In contrast with typical converters, this perform of reworking the ability provide isn't solely an essential benefit, but additionally an essential differentiation characteristic.

Determine 3: The quick load transient response of BCM6135 is the important thing to supporting 12V hundreds. The transient response is 8 million amperes per second (8MA/s). Yellow: enter voltage (800VDC), crimson: output voltage (48V), blue: output present.

Determine 4: Purposeful block diagram of BCM bus converter. Though BCM can carry out DC-DC conversion, it may well additionally use a transformer to carry out high-efficiency AC-AC conversion. Not solely can the dimensions be scaled by the Okay issue, but additionally the change module can be utilized to transform between AC and DC. The change is accomplished at a excessive frequency, and since it has the identical vitality switch traits as a transformer, the conversion can't solely reply shortly to transient load modifications, but additionally present a low impedance path between enter and output.

Vicor BCM can be utilized as a set ratio converter, the place the output voltage is a set ratio of the enter voltage. The Vicor BCM6135 converter is remoted and makes use of a 61 x 35 x 7 mm bundle to offer 2.5kW of energy with a peak effectivity of over 97%. It may be simply related in parallel within the array to offer extra energy.

The mounted ratio property of this BCM ensures that the digital battery stays inside its correct working vary. For instance, in an electrical automobile powered by an 800V battery, the high-voltage battery may be assured between 520 and 920V. The BCM6135 with a ratio of 1/16 can virtualize a 48V battery, making certain that the voltage vary is between 32.5 and 57.5V. The ratio of BCM6135 1/8 can be utilized for 400V electrical automobiles (Determine 3).

Battery virtualization can be prolonged to a 12V bus utilizing a 1/4 fixed-ratio converter. On this case, galvanic isolation isn't required, and Vicor NBM™ bus converters can be utilized. Like the opposite traits of BCM, the NBM non-isolated bus converter has all the benefits talked about above: quick transient response, low impedance and bidirectional operation. The voltage vary of the 12V bus is saved between 8.125V and 14.375V, and the ratio to the high-voltage battery voltage is mounted. BCM and NBM applied sciences are excellent transformers to attach the ability provide networks of vehicles.

Desk 1: The minimal and most voltages on the 48V bus and 12V bus utilizing Vicor BCM/NBM bus converter expertise. Each the 48V and 12V voltage ranges adjust to the VDA 320 and LV 124 requirements.

Determine 5: 12V and 48V battery virtualized E/E structure primarily based on BCM6135 and NBM2317 modules. The 48V bus can be used as a extra environment friendly energy supply to energy increased hundreds within the automobile, resembling air con condensers, water pumps, and energetic chassis stabilization techniques.

It's important to make sure the ability provide redundancy for functionally protected hundreds. The Vicor energy module is absolutely expandable by way of energy provide and transmission, so it may be designed as a redundant PDN, in order that it may well provide energy to the load that's crucial to practical security by way of two devoted energy conversion paths. Finally, OEM producers can implement localized vitality storage to make sure the protected operation of essential techniques resembling ADAS, steering and braking.

The place will the electrical automobile energy provide community go?

12V lead-acid batteries will quickly withdraw from the European market. Given that each one improvements have pushed the redesign of the electrical automobile energy provide community, this timing could be very applicable.

Automotive electrical PDN is on the crossroads of 12V energy provide. Whereas attempting to maintain the structure modifications to a minimal, increasingly more stringent energy hundreds are utilized to automobiles. Tesla CEO Elon Musk mentioned: “Why can we nonetheless use 12V? 12V is only a residual voltage, which is certainly too low.”

OEM producers are scrambling to design higher PDNs to offer electrical automobiles with higher mileage and better efficiency. The entire elimination of the 12V battery is clearly a long-term resolution, which not solely reduces weight and area, but additionally supplies higher transient response and system efficiency. Vicor expertise not solely realizes these benefits, but additionally supplies unparalleled flexibility, scalability and energy density. Vicor’s PDN module resolution supplies a perfect constructing block for fixing the latest challenges of the brand new technology of xEV’s 12V energy provide community.

Nicolas Richard
Vicor European Automotive Enterprise Improvement Director

Earlier than becoming a member of Vicor, Nicolas served as the top of the North American automotive enterprise division at IDT (Renesas Electronics), the place he was primarily engaged within the technical gross sales of energy techniques, infotainment techniques and ADAS techniques. Earlier than becoming a member of IDT, he served as a discipline software engineer at ON semiconductor for 4 years, main an inside design and software workforce (a “idea to product champion” workforce), accountable for ON Semiconductor’s automotive gross sales in Detroit, Michigan New product development technique. His work expertise additionally consists of 9 years of engineering and growth work at Continental Motors. Throughout this era, he held varied engineering design positions in Continental’s Hybrid and Electrical Automobiles division, primarily designing DC/DC converters and traction inverters. Changer.