CommercialToolry

All About Aurora Electric Bike: Specifications, Performance, and Common Uses

Types and Models of Aurora Electric Bikes

Aurora electric bikes are engineered in multiple body styles and configurations to suit a wide range of riding needs. Whether you're commuting through city streets, exploring rugged mountain trails, or seeking a compact solution for urban transport, Aurora offers a purpose-built e-bike for every lifestyle. With advanced motors, long-range batteries, and durable construction, these bikes blend performance, comfort, and innovation.

City E-Bikes

Designed for urban commuting, Aurora city e-bikes feature lightweight frames, narrow tires, and agile handling for navigating traffic and tight city streets with ease.

Advantages
  • Lightweight and easy to maneuver
  • Ideal for daily commuting
  • Often equipped with fenders, racks, and integrated lights
  • Smooth gear transitions for effortless riding
Limitations
  • Not suited for off-road terrain
  • Limited suspension for rough surfaces
  • Lower top speed compared to speed e-bikes

Example Model: Aurora City Commuter – 250W motor, 36V battery, up to 50 miles range

Folding E-Bikes

Perfect for urban dwellers and travelers, Aurora folding e-bikes combine portability with electric power, making them ideal for small apartments, public transit, and multi-modal commutes.

Advantages
  • Compact and easy to store
  • Lightweight and portable
  • Great for mixed transportation (bike + train/bus)
  • Maintains solid battery range despite size
Limitations
  • Slightly reduced stability due to smaller wheels
  • Assembly/disassembly required
  • Potential durability concerns with frequent folding

Best for: Apartment living, commuters using public transit, travelers

Mountain E-Bikes

Built for off-road adventures, Aurora mountain e-bikes feature rugged frames, full suspension systems, and aggressive tread tires to conquer trails, hills, and uneven terrain.

Advantages
  • Powerful motors for steep climbs
  • Enhanced traction and stability
  • Durable construction for rough use
  • Excellent shock absorption
Limitations
  • Heavier than city or folding models
  • Higher energy consumption
  • Less efficient on paved roads

Example Model: Aurora XT Mountain Bike – 750W motor, dual suspension, all-terrain tires

Hybrid E-Bikes

A versatile blend of road and mountain bike features, Aurora hybrid e-bikes are perfect for riders who want one bike for city streets, bike paths, and light off-road trails.

Advantages
  • Adaptable to multiple surfaces
  • Comfortable upright riding position
  • Good balance of speed and stability
  • Ideal for fitness and recreational use
Limitations
  • Not optimized for extreme off-roading
  • May lack advanced features of specialized models
  • Moderate weight due to versatility

Example Model: Aurora All-Terrain – Multi-surface tires, 500W motor, 45-mile range

Speed E-Bikes (Throttle-Enabled)

Also known as Class 3 e-bikes, Aurora speed e-bikes are built for fast, long-distance travel with throttle control that allows motor-only propulsion without pedaling.

Advantages
  • High top speed (up to 28 mph)
  • Reduced physical effort
  • Efficient for long commutes
  • Throttle control for instant acceleration
Limitations
  • Subject to local e-bike regulations
  • Higher battery consumption
  • May require a helmet or license in some areas

Example Model: Aurora Fast E-Bike – 28 mph top speed, pedal-assist + throttle, 40-mile range

Bike Type Motor Power Top Speed Best For Range (Approx.)
City E-Bike 250W 20 mph Daily commuting, urban rides 40–50 miles
Folding E-Bike 350W 20 mph Portability, small spaces 30–40 miles
Mountain E-Bike 750W 20 mph Off-road trails, rugged terrain 35–45 miles
Hybrid E-Bike 500W 20 mph Mixed surfaces, fitness riding 40–45 miles
Speed E-Bike 750W 28 mph Fast commutes, long distances 35–40 miles

Expert Tip: Always check local e-bike regulations before purchasing a speed e-bike (Class 3), as throttle-enabled models with speeds over 20 mph may have legal restrictions in certain cities or states. Helmet use and age limits may also apply.

How to Choose the Perfect Aurora Electric Bike

Selecting the right Aurora electric bike is a crucial decision that can significantly enhance your riding experience, whether you're commuting to work, exploring trails, or enjoying weekend leisure rides. With a wide range of models tailored for different terrains and rider needs, understanding the key selection criteria ensures you get the most value, comfort, and performance from your investment.

Key Factors to Consider When Choosing an Aurora E-Bike

Intended Usage

Your primary riding purpose should be the foundation of your decision. Aurora offers specialized e-bike categories designed for distinct environments and activities:

  • City Commuting: Aurora e-city bikes are lightweight, agile, and equipped with features like integrated lights and fenders—ideal for navigating urban traffic and short to medium-distance commutes.
  • Off-Road Adventures: For rugged trails and mountainous terrain, Aurora’s mountain e-bikes deliver superior durability, suspension systems, and enhanced traction with powerful motors and robust frames.
  • Versatile Riding: Aurora hybrid e-bikes strike a perfect balance between comfort and performance, making them excellent for mixed use—whether commuting on paved roads or exploring light trails.

Motor Power and Performance

The motor is the heart of any electric bike, directly influencing acceleration, hill-climbing ability, and overall responsiveness. Aurora e-bikes feature a range of motor options calibrated for different riding demands:

  • 250W Motors: Ideal for flat urban environments and casual riders. These provide efficient assistance up to legal speed limits in many regions, ensuring longer battery life and smoother integration with pedal effort.
  • 500W–750W Motors: Designed for challenging terrain, steep inclines, or riders carrying heavy loads. These high-torque motors deliver aggressive performance and are commonly found in Aurora’s mountain and cargo e-bike models.

Note: While higher motor power enhances performance, it may reduce battery efficiency. Choose based on your typical riding conditions and local regulations.

Battery Range and Charging

Battery range determines how far you can travel on a single charge, a critical factor for daily commuters and long-distance riders. Aurora e-bikes are equipped with advanced lithium-ion batteries offering varying capacities:

  • Standard models offer **40–60 km (25–37 miles)** of range—perfect for city commutes and errands.
  • Extended-range models can reach **80–120 km (50–75 miles)**, ideal for touring or rural riders who need less frequent charging.
  • Battery life depends on terrain, rider weight, assist level, and weather conditions.

Most Aurora batteries are removable, allowing convenient indoor charging. A full recharge typically takes 4–6 hours, and the battery management system ensures longevity and safety.

Bike Design and Rider Comfort

Comfort is essential, especially for extended rides. An ergonomically designed bike reduces fatigue and enhances control. Key comfort elements to evaluate include:

  • Saddle Quality: Look for gel-padded or adjustable seats that support long-duration riding.
  • Handlebar Position: Upright handlebars promote a relaxed posture, while drop or flat bars offer more control depending on the model.
  • Frame Geometry: Aurora provides detailed sizing charts to match your height and inseam, ensuring optimal fit and handling.
  • Suspension: Front or full suspension options absorb shocks on uneven surfaces, improving ride quality and control.

Test riding or virtual fit tools can help confirm comfort before purchase.

Additional Features and Accessories

Modern Aurora e-bikes come equipped with smart features that enhance convenience, safety, and functionality:

  • Integrated Lighting: Front and rear LED lights improve visibility and safety during early morning or evening rides.
  • Fenders and Racks: Essential for commuters—protect against mud and allow easy attachment of bags or cargo.
  • Advanced Braking Systems: Hydraulic disc brakes offer superior stopping power in all weather conditions, especially important at higher speeds.
  • Smart Displays: LCD or LED dashboards show speed, battery level, assist mode, trip distance, and more, giving riders full control and feedback.
  • Bluetooth Connectivity: Some models support app integration for ride tracking, diagnostics, and firmware updates.

Weight, Portability & Build Quality

While e-bikes are inherently heavier than traditional bikes due to the motor and battery, Aurora optimizes weight distribution for manageable handling:

  • City models typically weigh **18–22 kg (40–48 lbs)**.
  • Mountain and cargo models may range from **25–30 kg (55–66 lbs)**.
  • Aluminum frames provide a strong yet lightweight structure, resistant to corrosion.

Consider storage space and whether you’ll need to lift the bike onto racks or into vehicles. Folding models or those with removable batteries offer added portability.

Selection Factor Recommended for Aurora Model Examples
Urban Commuting Daily travel, stop-and-go traffic, short distances Aurora CityRide 250, MetroGlide
Hilly Terrain Steep inclines, rugged roads Aurora TrailBoost 750, SummitX
Leisure & Fitness Parks, bike paths, weekend rides Aurora HybridFlex, TerraCruiser
Long-Distance Touring Extended trips, minimal charging access Aurora EnduroMax, Voyager Pro

Important: Always match your Aurora e-bike choice to your riding environment, physical needs, and local e-bike regulations. Overlooking factors like motor wattage limits or helmet requirements can lead to legal or safety issues. Consult Aurora’s official website or an authorized dealer for up-to-date specifications, warranty details, and test ride availability. Proper selection today ensures years of reliable, enjoyable riding tomorrow.

Benefits of Aurora Electric Bikes

Aurora electric bikes offer a transformative way to travel, combining innovation, sustainability, and performance into a single, user-friendly package. More than just a mode of transportation, these e-bikes are designed to enhance daily life—whether you're commuting to work, running errands, or enjoying weekend adventures. Backed by cutting-edge technology and ergonomic design, Aurora e-bikes deliver a seamless riding experience that appeals to urban dwellers, fitness enthusiasts, eco-conscious riders, and casual cyclists alike.

Sustainability

Aurora e-bikes are a powerful step toward a greener future. As zero-emission vehicles, they produce no tailpipe pollutants or greenhouse gases, making them an environmentally responsible alternative to gas-powered cars and motorcycles.

  • Reduces individual carbon footprint significantly—up to 50% less CO₂ per mile compared to driving
  • Decreases urban air pollution, contributing to cleaner, healthier cities
  • Powered by rechargeable lithium-ion batteries that are recyclable and energy-efficient
  • Encourages a shift away from fossil fuel dependency, supporting global climate goals

Did you know? Replacing just one car trip per week with an e-bike can save over 250 kg of CO₂ emissions annually.

Cost-Effectiveness

While the upfront investment in an Aurora e-bike may seem higher than a traditional bicycle, the long-term savings are substantial—especially when compared to car ownership and public transit costs.

  • No fuel expenses—charging costs as little as $0.02 per full charge
  • Minimal maintenance: no oil changes, transmission repairs, or engine servicing
  • Lower insurance and registration fees (in most regions)
  • Eligible for government incentives, tax credits, and rebates in countries like the U.S., Canada, Germany, and France
  • Saves on parking fees and tolls commonly associated with car use

Smart savings: Over five years, e-bike owners can save thousands compared to car commuting.

Health Benefits

Contrary to the misconception that e-bikes do all the work, Aurora e-bikes promote active living by making cycling accessible and enjoyable for people of all fitness levels.

  • Provides moderate aerobic exercise that improves cardiovascular health and lung capacity
  • Builds leg strength and core stability through regular pedaling, even with electric assist
  • Burns 300–500 calories per hour, depending on terrain and effort level
  • Encourages longer and more frequent rides due to reduced fatigue, increasing overall physical activity
  • Ideal for rehabilitation, older adults, or those returning to fitness with low-impact exercise

Pro tip: Use lower assist levels to increase workout intensity while still conquering hills and headwinds.

Convenience

Aurora e-bikes are engineered for real-world usability, offering unmatched convenience in urban and suburban environments.

  • Effortless hill climbing and headwind resistance thanks to powerful, responsive motors
  • Arrive at work or appointments without excessive sweating, ideal for daily commutes
  • Compact design allows for easy storage at home or in the office—no garage needed
  • Integrated smart features: LCD displays, GPS tracking, Bluetooth connectivity, and app-based ride analytics
  • Foldable or lightweight models available for easy transport on public transit or in cars

Time-saver: E-bikes can be up to 3x faster than walking and often outperform cars in congested city traffic.

Versatility

One of the standout features of Aurora e-bikes is their adaptability to a wide range of lifestyles, terrains, and purposes.

  • Commuting: Ideal for urban riders navigating traffic and public transit bottlenecks
  • Recreation: Perfect for weekend trails, park rides, and family outings
  • Off-Road: Mountain and fat-tire models handle rugged trails and snowy paths with ease
  • Utility: Cargo and folding models support grocery runs, school drop-offs, and small deliveries
  • Available in step-through, step-over, folding, and cargo configurations to suit different needs

Key advantage: A single Aurora e-bike can replace multiple transportation methods in your daily routine.

Additional Benefits

Beyond the core advantages, Aurora e-bikes offer several lifestyle-enhancing features that improve safety, connectivity, and enjoyment.

  • Reduced Traffic Stress: Avoid congestion and parking hassles common in urban areas
  • Increased Independence: Offers mobility for those who can’t drive or rely on public transit
  • Fun and Freedom: Rediscover the joy of riding with speed, comfort, and confidence
  • Community Engagement: Join growing e-bike communities and eco-conscious networks
  • Quiet Operation: Enjoy peaceful rides without engine noise or vibrations

Bonus: Many Aurora models include integrated lights, fenders, racks, and anti-theft systems for complete out-of-the-box readiness.

Expert Insight: Aurora e-bikes are not just a transportation upgrade—they're a lifestyle enhancement. Whether you're looking to save money, improve your health, reduce your environmental impact, or simply enjoy the ride more, these e-bikes deliver measurable benefits across all areas of daily life. For first-time buyers, consider starting with a mid-range commuter model to experience the full advantages before exploring specialized variants.

Use Case Recommended Aurora Model Key Feature Estimated Cost Savings (Annual)
Daily Commute (10–15 miles) Aurora CityRider Pro Integrated lights & navigation display $800–$1,200
Weekend Trail Riding Aurora TrailBlaze X All-terrain tires & suspension fork N/A (replaces costly gear rentals)
Family Errands & Shopping Aurora CargoGo Front cargo rack & child seat compatibility $600–$900
Fitness & Recreation Aurora FitCycle Heart rate monitor & fitness tracking app N/A (health benefit value: $500+ in gym memberships)

Why Aurora Stands Out

  • Advanced Motor Systems: Smooth, quiet mid-drive or hub motors with multiple assist levels
  • Long-Lasting Batteries: High-capacity lithium-ion batteries offering 40–80 miles per charge
  • Durable Construction: Aerospace-grade aluminum frames built to last over 10 years with proper care
  • Customer Support: Comprehensive warranty (2–5 years), service network, and online resources
  • Innovation: Regular firmware updates and smart integration for future-ready performance

Complete Maintenance & Repair Guide for Aurora Electric Bikes

Proper maintenance and timely repairs are essential for maximizing the lifespan, performance, and safety of your Aurora electric bike. With a combination of routine care and periodic inspections, you can ensure smooth rides, optimal battery efficiency, and reliable operation in all conditions. This comprehensive guide covers all critical aspects of e-bike upkeep—from daily checks to professional servicing—so you can keep your Aurora e-bike in peak condition year after year.

Safety Reminder: Always turn off the power and disconnect the battery before performing any maintenance or repairs. Work in a dry, well-lit area and avoid exposing electrical components to moisture. Use manufacturer-recommended tools and replacement parts to maintain warranty coverage and ensure compatibility.

Essential Maintenance Tasks for Aurora E-Bikes

  • Regular Cleaning and Drivetrain Care

    Keeping your Aurora e-bike clean is fundamental to preventing premature wear and corrosion. Regularly wipe down the frame with a damp cloth and mild detergent, avoiding high-pressure water that could damage electrical components.

    The chain, cassette, and derailleur should be cleaned and lubricated every 100–150 miles or after riding in wet or dusty conditions. Use a bicycle-specific chain lube and wipe off excess to prevent dirt buildup. Inspect the chain for stretch using a chain checker tool—replace it if it exceeds 0.75% wear to avoid damaging the drivetrain.

    Pay special attention to the motor housing and battery compartment. While the battery is generally water-resistant, avoid direct spraying or submersion. Never clean the motor internals—only wipe the exterior with a dry or slightly damp cloth.

  • Battery Maintenance and Charging Best Practices

    The battery is the heart of your e-bike’s performance. To extend its lifespan, charge it when it reaches 20–30% capacity and avoid letting it drop to 0%. Similarly, unplug the charger once it reaches 100% to prevent overcharging, which can degrade lithium-ion cells over time.

    For long-term storage (over one month), charge the battery to approximately 50–60% and store it in a cool, dry place between 50°F and 77°F (10°C–25°C). Avoid leaving the battery in hot vehicles or unheated garages during winter, as extreme temperatures significantly reduce capacity and longevity.

    Inspect the battery casing for cracks, swelling, or corrosion on the terminals. If any abnormalities are found, discontinue use and contact Aurora customer support. Always use the original charger to prevent voltage mismatches and potential safety hazards.

  • Tire Pressure and Tread Inspection

    Maintaining correct tire pressure is crucial for ride comfort, traction, and energy efficiency. Under-inflated tires increase rolling resistance, reducing battery range and increasing the risk of pinch flats. Over-inflated tires reduce grip and lead to a harsher ride.

    Check tire pressure weekly using a reliable floor pump with a gauge. Refer to the sidewall of the tire for the recommended PSI range (typically 40–65 PSI for e-bikes). Adjust based on rider weight and terrain—lower pressure for off-road or wet conditions, higher for paved roads.

    Inspect tires monthly for cuts, embedded debris, bulges, or uneven tread wear. Replace tires if the tread is worn down to the wear indicators or if the casing is exposed. Consider using puncture-resistant tires for longer durability, especially if you commute regularly.

  • Brake System Inspection and Adjustment

    Safety begins with reliable braking. Aurora e-bikes typically come equipped with hydraulic disc brakes or mechanical disc brakes, both of which require regular inspection.

    Check brake pads monthly for wear. Replace them if the friction material is less than 1mm thick. Look for uneven wear, which may indicate caliper misalignment. Listen for squealing or grinding noises—these often signal contamination or worn pads.

    Ensure brake levers feel firm and responsive. If the lever reaches the handlebar, bleed hydraulic brakes to remove air bubbles or adjust cable tension on mechanical systems. Inspect brake lines and cables for kinks, fraying, or leaks. Replace damaged components immediately.

    Test brakes at low speed before each ride. Perform a “pinch test” on the rotor to ensure it spins freely without rubbing.

  • Professional Servicing and Advanced Diagnostics

    While many maintenance tasks can be performed at home, annual professional servicing is strongly recommended. A certified technician can conduct a full diagnostic of the motor, controller, display unit, and wiring harness—components that are not user-serviceable.

    During a service visit, the technician will:

    • Inspect motor function and torque sensor calibration
    • Check for error codes via the onboard diagnostics system
    • Test battery health and cell balance
    • Lubricate internal drivetrain components (if applicable)
    • Calibrate pedal-assist levels and throttle response
    • Update firmware if new versions are available

    Scheduling a professional tune-up each year helps catch hidden issues early, maintains warranty eligibility, and ensures your e-bike operates at peak efficiency.

Maintenance Task Frequency Tools Needed Key Indicators for Service
Chain Lubrication & Cleaning Every 100–150 miles or after wet rides Chain cleaner, lube, rag Chain squeaks, rust, visible dirt buildup
Battery Charging & Storage After each ride / monthly for storage Original charger, voltage meter Swelling, slow charging, reduced range
Tire Pressure Check Weekly Floor pump with gauge Low range, poor handling, frequent flats
Brake Pad Inspection Monthly Hex wrench, flashlight Squealing, reduced stopping power, thin pads
Full Professional Service Annually or every 1,000 miles N/A (performed by technician) Motor hesitation, error codes, connectivity issues

Expert Tip: Keep a simple maintenance log noting dates of battery charges, tire pressure checks, and component replacements. This record helps identify patterns, anticipate future repairs, and supports warranty claims if needed.

Additional Tips for Long-Term E-Bike Health

  • Always power down the system before cleaning or transporting the bike
  • Avoid locking the bike outdoors overnight; use a weatherproof cover if necessary
  • Recharge the battery every 2–3 months if the bike is not in use
  • Register your Aurora e-bike and keep firmware updated via the official app (if supported)
  • Use only Aurora-approved accessories and replacement parts to ensure compatibility
  • Report unusual noises, error messages, or performance drops promptly to avoid costly repairs

By following this detailed maintenance plan, you’ll not only extend the life of your Aurora electric bike but also enjoy a safer, smoother, and more efficient riding experience. Remember: consistent care today prevents major repairs tomorrow. When in doubt, consult the official Aurora owner’s manual or reach out to an authorized service center for expert assistance.

Frequently Asked Questions About Aurora Electric Bikes

Q1: What is the range of an Aurora electric bike?

A1: The range of an Aurora electric bike varies depending on the specific model, terrain, rider weight, and the level of pedal assist used. On average, most Aurora e-bikes can travel between 20 and 50 miles on a single full charge.

  • Eco Mode: Offers the longest range (up to 50 miles) by providing minimal motor assistance, ideal for flat terrain and energy conservation.
  • Normal Mode: Balances power and efficiency, typically delivering 30–40 miles of range.
  • Turbo/High Mode: Maximizes motor output for steep hills or faster acceleration, reducing range to around 20–25 miles.

Factors like tire pressure, wind resistance, and riding style also impact battery efficiency. For optimal performance, keep tires properly inflated and avoid aggressive riding when maximizing range is a priority.

Q2: Can I ride my Aurora e-bike in the rain?

A2: Yes, Aurora electric bikes are designed with weather-resistant components, allowing safe operation in light to moderate rain. However, riders should take precautions to protect the bike’s electrical systems.

  • Water Resistance Rating: Most Aurora models feature IPX4 or higher protection, meaning they are splash-resistant from any direction but not fully waterproof.
  • Avoid Submersion: Never submerge the motor, battery, display, or wiring connectors in water. Puddles and wet roads are generally safe, but avoid deep积水 or high-pressure washing.
  • Post-Ride Care: After riding in wet conditions, gently wipe down the bike and allow it to dry in a sheltered area to prevent corrosion and moisture buildup.
  • Storage Tip: Always store your e-bike indoors or under cover after riding in the rain to prolong the life of electronic and mechanical parts.

While short rides in drizzle are acceptable, prolonged exposure to heavy rain or storms is discouraged to maintain long-term reliability.

Q3: How do I store my Aurora e-bike when not in use for a long time?

A3: Proper long-term storage is essential to maintain battery health and overall performance. Follow these best practices for storing your Aurora e-bike:

  • Battery Charge Level: Charge the battery to approximately 50% before storage. A fully charged or completely drained battery can degrade faster over time.
  • Storage Environment: Keep the bike in a cool, dry place with stable temperatures—ideally between 50°F and 77°F (10°C–25°C). Avoid garages or sheds with extreme temperature swings.
  • Battery Removal: If possible, remove the battery and store it separately in a protective case to reduce strain on the electrical system.
  • Monthly Check: Recharge the battery to 50% every 2–3 months during storage to prevent deep discharge and maintain cell longevity.
  • Physical Protection: Cover the bike to prevent dust accumulation and keep tires slightly inflated to avoid flat spots.

Following these steps can significantly extend the lifespan of your e-bike and ensure it's ready to ride when you are.

Q4: Are Aurora electric bikes suitable for all heights?

A4: Aurora electric bikes are available in multiple frame sizes to accommodate a wide range of rider heights, ensuring comfort, control, and proper ergonomics for most adults.

Frame Size Rider Height Range Recommended Use
Small (15–16 inches) 4'10" – 5'4" (147–163 cm) Compact riders, urban commuting, shorter torsos
Medium (17–18 inches) 5'5" – 5'9" (165–175 cm) General use, fitness riding, average build
Large (19–20 inches) 5'10" – 6'1" (178–185 cm) Taller riders, long-distance comfort
Extra Large (21+ inches) 6'2" and above (188+ cm) Extended leg reach, taller frames

When selecting a model, refer to the manufacturer’s size guide and consider test-riding the bike if possible. Adjusting the seat height and handlebar position can further customize fit. Ensuring the correct frame size enhances safety, pedaling efficiency, and overall riding enjoyment.

Q5: How long does it take to charge an Aurora e-bike fully?

A5: Most Aurora e-bike batteries take between 4 to 6 hours to charge from empty to full using the included smart charger. Charging time may vary slightly based on battery capacity, age, and ambient temperature.

  • Fast Charging Options: Some newer Aurora models support partial fast charging, reaching 80% capacity in about 3 hours for quicker turnaround.
  • Charger Type: The standard charger is a 42V or 54.6V lithium-ion compatible unit with automatic shut-off when fully charged, preventing overcharging.
  • Optimal Charging Conditions: Charge in a dry, room-temperature environment. Extremely cold or hot conditions can slow charging and reduce battery efficiency.
  • Battery Longevity Tip: Avoid leaving the battery plugged in for extended periods after it reaches 100%. Unplug once charging is complete to maximize battery cycle life.

For daily riders, charging overnight is convenient and ensures a full battery each morning. Occasional users can charge as needed, but it's recommended to keep the battery above 20% to avoid deep discharge.