What Is The Audi Long Bess Battery System?
The Audi Long Bess Battery System is a high-capacity lithium-ion energy storage solution engineered for Audi’s electric vehicles (EVs), prioritizing energy density and longevity. Built with nickel-manganese-cobalt (NMC) cells, it delivers 350–400 Wh/kg efficiency and integrates advanced thermal management for optimized performance in Audi e-tron models. Its modular design supports 800V architectures, enabling ultra-fast DC charging (10–80% in 22 minutes) while maintaining cycle stability beyond 2,000 charges.
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What defines the Audi Long Bess Battery System?
The Audi Long Bess combines NMC 811 cells arranged in 192s3p configurations, achieving 95 kWh gross capacity. Its liquid-cooled modular trays minimize voltage sag under load, sustaining 270 kW peak discharge. Pro Tip: Avoid deep discharges below 10%—it accelerates cathode degradation in high-nickel chemistries.
Unlike standard EV packs, the Long Bess uses prismatic cells with laser-welded busbars, reducing internal resistance by 15%. For example, Audi’s e-tron GT leverages this system for 238-mile EPA range. But how does it handle extreme temperatures? Dual-loop cooling maintains 25–40°C cell temps even during track-mode driving. A 12V lithium backup ensures BMS stability during rapid charging. Key Specs: 798V nominal voltage, 650A max continuous current, 2,200 W/kg specific power.
How does thermal management enhance performance?
The dual-loop cooling system separates power electronics and battery cooling, using 50/50 glycol-water mix. Variable-speed pumps adjust flow rates based on cell temperature differentials, ensuring ±2°C uniformity. Pro Tip: Precondition the battery via the Audi app before DC fast charging to reduce cell stress.
During fast charging, coolant circulates at 8 liters/minute, dissipating 6 kW of heat. Practically speaking, this prevents throttling even in 40°C ambient temperatures. For context, Tesla’s octovalve system manages similar loads but lacks Audi’s dual-loop redundancy. A cold plate under each module absorbs heat through aluminum fins, while refrigerant lines cool the coolant itself. Real-World Impact: In winter, the system preheats cells to 15°C using waste heat from the drivetrain, preserving range.
| Feature | Audi Long Bess | Competitor X |
|---|---|---|
| Coolant Flow Rate | 8 L/min | 5 L/min |
| Temp Uniformity | ±2°C | ±5°C |
Why is modular design critical for scalability?
Modular tray-based architecture allows Audi to stack 12–36 cell modules per pack, adapting capacity from 85 kWh to 120 kWh. Each 6.5 kWh module has independent voltage monitoring, enabling rapid fault isolation. Pro Tip: Replace modules in pairs to maintain impedance matching.
Imagine building with LEGO bricks: Audi can swap modules for different chemistries (e.g., switching to LFP for fleet vehicles). This design also simplifies repairs—dealerships replace single trays instead of entire packs. But what about weight distribution? The Long Bess positions modules low in the chassis, improving center of gravity by 30 mm versus non-modular designs. Key Specs: 23 modules per base pack, 2.2-ton total weight, IP67 ingress protection.
How does the 800V architecture benefit charging?
Audi’s 800V electrical system halves charging time by doubling voltage, reducing current to 375A at 270 kW. Silicon-carbide inverters minimize switching losses, achieving 97% efficiency. Pro Tip: Use only Audi-certified 800V chargers—third-party units may lack voltage stabilization.
At a 350 kW DC station, the Long Bess adds 180 miles in 15 minutes. Comparatively, 400V systems require 30+ minutes for the same gain. However, can home chargers support 800V? Most Level 2 units max out at 240V, but Audi’s onboard booster converts AC to 800V DC internally. Example: The 2024 e-tron SQ7 charges 10–80% in 22 minutes, leveraging Porsche’s cross-compatible infrastructure.
| Parameter | 800V System | 400V System |
|---|---|---|
| Charging Time (10–80%) | 22 min | 45 min |
| Cable Thickness | 18 mm | 25 mm |
What safety mechanisms prevent failures?
Multi-layer BMS monitors cell voltage, temperature, and impedance 100x/second. Pyrofuse disconnects isolate faults within 3 ms, while ceramic separators prevent dendrite penetration. Pro Tip: Annual BMS firmware updates optimize safety algorithms.
In crash scenarios, the pack’s aluminum honeycomb structure absorbs impact, reducing cell deformation by 70%. The BMS also triggers a 500V isolation relay, disconnecting the HV system. For instance, during a simulated side collision, the Long Bess shut down 40% faster than EU regulations require. Beyond physical safeguards, machine learning predicts cell aging patterns, alerting users to replace modules before failure.
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FAQs
No—it requires 800V platforms like the PPE architecture. Retrofitting older 400V models risks inverter damage.
How much does a Long Bess replacement cost?
Approx. $22,000–$28,000, including labor. Audi offers prorated warranties covering 70% capacity for 8 years.
Does cold weather reduce its range?
Yes, by 18–25% at -10°C. Preconditioning via the app cuts losses to 12%.