What sparks will fly from the potential merger between Nissan and Honda? Recent reports indicate that these two automakers are in talks to integrate their businesses, aiming to bolster their operational capabilities and compete globally with Tesla and Chinese new energy vehicle companies. While the final form of their collaboration remains undecided, an official announcement is expected as early as next month. If successful, this alliance could have a market base exceeding 8 million vehicles. Achieving such sales expectations will undoubtedly rely on more than just traditional fuel vehicles; the core of this merger lies in creating new hybrid and pure electric vehicle models. So, what innovative technologies will these Japanese automakers bring to the table when they join forces?

Will Honda's i-MMD technology incorporate a P4 motor to become a plug-in hybrid, or will Nissan's e-POWER utilize Honda's engine for extended range? Post-merger, Nissan and Honda are expected to share technologies and components to a great extent. This includes Honda's fourth-generation i-MMD and Nissan's e-POWER, both of which will undergo further optimization. How will this unfold? Market demand dictates technology, and China's hybrid market currently demands lower fuel consumption in electric-only mode and increased pure electric and combined driving ranges. In summary, the entire power system must "consume less and travel farther." To balance energy consumption and range, an appropriate battery capacity must be chosen to maximize engine efficiency. Therefore, in plug-in hybrid technologies with series-parallel architectures, small-capacity batteries are rarely used. Due to the inclusion of series mode, plug-in hybrid dedicated engines are essentially range extenders. Other mainstream technologies focus on reducing loss, improving power response, and optimizing NVH. Understanding the essence of mainstream hybrid technologies, let's delve into Honda and Nissan's offerings. The fourth-generation i-MMD and e-POWER share two similarities: a near-pure electric driving experience and the use of small battery solutions.

Honda's fourth-generation i-MMD primarily consists of a 2.0L Atkinson cycle naturally aspirated engine and a dual-motor hybrid system. Note that the dual motors are not independent but rather a dual-motor unit parallel to the engine crankshaft, with one motor dedicated to power generation and the other to driving. The dual-axle layout allows for high-power, large-size motors, but they remain on the front axle. Power distribution and speed regulation are managed by a clutch for electromechanical coupling. Essentially, this solution does not utilize a DHT hybrid transmission or independent motors. Four-wheel drive is achieved through a drive shaft. The power unit prioritizes miniaturization and high integration.

The battery discharges only during startup and low speeds. After acceleration or when the battery is depleted, the engine collaborates with the generator to recharge. Direct drive engages during rapid acceleration and cruising. The system primarily operates on electricity, with the engine playing a significant role in most conditions. Initially designed for gasoline-electric hybrids, this technology did not consider large battery solutions. Although an 18 kWh battery was later introduced for external charging, it significantly impacts cabin space. For instance, the trunk of the Accord e:PHEV has a noticeable raised step, affecting practicality and weight distribution. Smaller batteries also do not support high-rate charging efficiency.

Nissan's e-POWER is a typical small-battery series hybrid architecture comprising a three-cylinder variable compression ratio engine, an electric motor, and a 2.1 kWh battery. The 1.5T version features front and rear dual motors, while the 1.2L version lacks a rear motor. The primary difference from mainstream series range extender technologies lies in the battery, which cannot be externally charged or store energy. The power unit essentially derives from the engine, with high demands on power transmission efficiency under various operating conditions. In other words, the combined range of e-POWER is entirely determined by engine efficiency and fuel tank capacity, making it challenging to exceed 1,000 kilometers. Thus, the first step in reforming Honda and Nissan's hybrid technologies is abandoning the small battery strategy. The first emerging technology is battery-chassis integration, supporting large-capacity battery packs without encroaching on cabin space.

The second new technology is likely to be a plug-in hybrid based on Honda's fourth-generation i-MMD. With a large battery pack strategy, the mechanical drive shaft becomes unnecessary. To create a four-wheel-drive version, a P4 motor must be added to the rear axle. Why not P2 or P3? The answer lies in the solution's essence: there is no large-volume transmission that can integrate a motor behind the engine, hence no planetary gear for power splitting. Instead, it relies on a clutch for electromechanical coupling. This leads to two possibilities: first, retaining the dual-axle dual-motor setup without decoupling the P1 generator, creating a misalignment with Volvo's decoupled P1+P4 solution. The front axle drive motor powers the front wheels, while the rear axle's P4 motor powers the rear wheels, achieving electric four-wheel drive without a drive shaft. Second, reverting to a coaxial single motor on the front axle, with pure electric power provided solely by the P4 motor. In both cases, the generator participates in direct drive. This not only avoids technological overlap with mainstream domestic plug-in hybrid solutions but also benefits from reduced wear due to electromechanical coupling, conducive to fuel economy. Imagine if the Sylphy adopted this plug-in hybrid solution; wouldn't its combined fuel economy be even lower? Crucially, an independent P4 motor can provide greater horsepower, resulting in faster acceleration.

The third new technology is likely to be a range-extended technology based on Nissan's e-POWER. Due to R&D, manufacturing, design, testing, and other costs, redesigning a range extender is virtually impossible. The most feasible solution currently appears to be converting Honda's LFB hybrid-dedicated engine into a range extender. This is technically feasible and likely to outperform Nissan's existing small-displacement variable compression ratio engine. Currently, mainstream range extenders in China have displacements of 1.5T or 2.0T and employ advanced technologies such as deep Miller cycles, 350Bar high-pressure direct injection, ultra-high-energy ignition, variable geometry turbochargers, EGR, variable oil pumps, active piston stop control, manifold injection, direct injection, or overhauling the entire cylinder block structure to follow the principle of large bore and long stroke.

From F1 racing cars to civilian vehicles, Honda's VTEC technology adjusts valve timing and lift based on throttle opening, enhancing combustion efficiency and power output. How about heat dissipation and intake and exhaust efficiency? Besides using a double-walled water jacket for temperature control, variable timing control on both intake and exhaust sides makes the intake and exhaust intelligent, enabling intelligent synergy between the engine and valve train. How about vibration? The answer lies in the high-strength crankshaft and dual balance shafts, which directly cancel out first- and second-order vibrations, improving NVH levels. The Atkinson cycle and Miller cycle work in opposite ways, so Honda's naturally aspirated engine does not lose torque in the high RPM range. According to this characteristic, the most efficient combustion speed matching BSFC (brake-specific fuel consumption) is fixed for direct power generation.

Will Nissan's expertise in battery safety solutions allow post-merger pure electric vehicles to focus on performance and handling? Besides battery-chassis integration and readjusting plug-in hybrids and range extenders, a fourth new technology may emerge post-merger, specifically focused on pure electric vehicles. Nissan's core technology in this area is battery safety. For example, the Nissan Leaf was once the world's best-selling pure electric vehicle, with a cumulative sales of 648,000 units and 21 billion kilometers driven without a single spontaneous combustion incident. Therefore, post-merger, Nissan's role in the pure electric field may primarily focus on battery safety.

Nissan's battery safety solutions are similar to those of mainstream domestic electric vehicle companies, focusing on enhancing cell and external structure integrity. For example, dual-component polyurethane automatic dispensing ensures cell safety and durability. The integrated aluminum battery compartment features six reinforced aluminum pillar beams to enhance resistance to compression and collision, protecting internal cells and modules. The battery compartment houses a double-stacked module with unique double bumpers and three 1500 MPa ultra-high-strength steel beams. The chassis is covered with resin armor to prevent deformation under pressure. The wet-dry separated integrated liquid thermal management system keeps the battery in optimal working condition.

Regarding the electric drive system, it is likely that the TZ220XS series, also used in the Xiaomi SU7, will continue to be adopted. With a starting power of 200 kW, it undoubtedly follows the high-horsepower motor approach. Therefore, the pure electric products of the alliance between the two Japanese automakers will continue to use Honda's existing e:Architecture W platform, which inherently supports high-performance electric drives, large-capacity high-density batteries, and dedicated pure electric vehicle frames. Consequently, a high-horsepower motor combined with a large battery pack will be selected, naturally leading to high-rate fast charging. This aligns with Honda's new domestic brand, Ye, which offers rear-wheel-drive single-motor and four-wheel-drive dual-motor options. Therefore, it's not excluded that a single-motor option may be introduced for extreme cost-effectiveness, with the focus on dual-motor four-wheel drive. How should this be understood? In terms of chassis hardware configuration, this platform directly provides front double wishbones and rear five-link suspensions, both known for their characteristics and widely used in new energy vehicles. They offer higher tuning limits for comfort or handling. The 12,000-ton integrated die-casting process reduces welding points while enhancing body torsional strength, also a cost-saving measure. Upon review, it becomes evident that the platform emphasizes driving pleasure through high rigidity, low center of gravity, lightweight design, high horsepower, and suspensions capable of handling both lateral and longitudinal stresses.

Will air suspensions and CDC damping be used to further enhance comfort? This solution is unlikely because the e:Architecture W platform already considers body roll suppression and stability. Instead, it features double vibration isolation on the front subframe, utilizing 3D gyroscope control and an ADS adaptive damping system to isolate road vibrations. Technically, the ADS adaptive system also belongs to damping technology that adjusts damping by controlling fluid. Simply put, it regulates the size of holes and slits within the shock absorber via solenoid valves, thereby changing the damping force. In a firmer mode, reducing the holes and slits increases oil flow resistance, providing greater damping rebound, suitable for aggressive driving scenarios. Conversely, in a softer mode, enlarging the holes and slits slows down oil flow, resulting in a longer rebound stroke and enhanced comfort.

Essentially, this chassis system remains passive. Compared to more mainstream active suspensions, it lacks sensors to monitor road conditions and radar or other intelligent driving perception hardware for advanced adjustment. However, given the SDV technology cooperation between the two parties, subsequent changes cannot be ruled out. Nevertheless, with the increasing cost pressure faced by Honda and Nissan, will these new technologies be implemented promptly and smoothly?