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SigmasTek  |  SKU: BW-18802

Mainstream MS9B High Performance Replacement Battery

Sale price $51.79 USD Regular price $65.84
Shipping calculated at checkout.

➤ Maintenance-free AGM design eliminates the need for acid filling

➤ Spillproof and leakproof for safe, hassle-free use

➤ U.L. recognized and CE certified for quality and safety assurance

➤ Superior starting power with deep cycle capacity for reliable performance

➤ Extreme resistance to freeze, heat, and vibration ensures durability


📦🚀 FAST SHIPPING: Usually ships same day if ordered before 2 PM EST

⚠️ Quick Reminder

🔹 Please ensure the original battery model number is listed in our product description and that your device model number matches for compatibility.
🔹 We only supply the batteries shown in the images. Device images are provided for reference only.

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Battery Care Guide

Battery Usage and Maintenance Guidelines 🔋

Please read the following instructions carefully before using your new battery. Proper adherence will help ensure optimal performance and extended service life.

1. Cordless Phones, PDAs, and Power Tools (NiMH, NiCd, Lithium-Ion) 📱

Initial Charge

  • Fully charge the battery overnight prior to first use.

Conditioning (First 2–6 Charge Cycles)

  • Operate the device until the battery reaches approximately 20% capacity.
  • Avoid premature recharging.
  • Do not allow the battery to fully discharge during the initial cycles.

Post-Conditioning

  • Recharge the battery only when necessary.
  • These batteries are capable of approximately 500 charge cycles:
  • Once daily → ~500 days
    Twice daily → ~250 days
    Note: Even a partial recharge is considered a full cycle.

2. Sealed Lead Acid (SLA) Batteries 💡

  • No conditioning required.
  • Maintain the battery in a fully charged state; avoid complete discharge.
  • Capable of 300–400 charge cycles.
  • Expected service life: 2–3 years, depending on usage conditions.

3. Laptop Batteries (Lithium-Ion) 💻

Initial Charge

  • Fully charge the battery overnight prior to first use.

Conditioning (First 2–6 Charge Cycles)

  • Charge fully, then discharge to approximately 20% capacity.
  • Avoid complete discharge, as some devices may not detect a fully drained battery.

Post-Conditioning

  • Minimize frequent plugging and unplugging.
  • Allow the battery to discharge moderately at least once per month to maintain optimal performance.
  • Occasional cycling is recommended to sustain battery health.

Professional Recommendation

Adhering to these guidelines will enhance battery longevity and ensure reliable performance.

For further assistance regarding your battery or order, our customer support team is available to provide guidance.

Delivery and Shipping

Everything You Need to Know About Shipping with BatteryWeb (USA)

We know reliable delivery matters when you need power fast. Here’s how BatteryWeb makes shipping easy across the USA:

🚚 Shipping & Delivery

Most orders ship next business day (some products like sealed lead acid may take a little longer).

Same-day shipping available if you order before 11:59 AM (delivery depends on the carrier).

We ship nationwide using FedEx, UPS, USPS, DHL, and regional ground carriers.

Shipping costs are calculated automatically at checkout based on weight, distance, and carrier.

Transit times shown are estimates only (business days, no weekends/holidays).

🌍 Shipping Restrictions

Lithium batteries cannot be shipped by USPS or air. They must go via FedEx Ground, UPS Ground, or DHL Ground.

PO Box deliveries are only available via USPS.

At this time, we do not ship lithium batteries to Puerto Rico. NiMH, NiCd, and Alkaline can be shipped.

📦 Important Notes

Double-check your shipping address! If an incorrect address is used and the order is returned, re-shipping costs are the buyer’s responsibility.

If a product is temporarily out of stock, we’ll notify you right away with the expected restock date—or issue a refund if you prefer.

💲 Currency & Pricing

All prices are shown in USD.

Orders shipped outside the USA may be subject to local taxes, customs fees, or import duties. These are the buyer’s responsibility.

⚡ At BatteryWeb, we’re committed to getting your batteries delivered quickly, safely, and affordably—so you’ll always have the power you need, when you need it.

Disclaimer

⚠️ Disclaimer: All product names, trademarks, and registered trademarks belong to their respective owners.

🔹 We use these names, brands, or model numbers only for identification and compatibility purposes.

🔹 Our products are generic replacement parts and are not affiliated with, endorsed by, or manufactured by the original equipment manufacturers (OEMs).


Volts & Amps

12 Volts | 8 AH

Terminal Type

Nut & Bolt

Replacement Mainstream MS9B Motorcycle Battery (Compatible MS9B)

This compatible replacement Mainstream MS9B battery provides compatibility, durable operation, and maintenance-free convenience for your motorcycle. Featuring AGM technology, this replacement battery removes the need for acid maintenance while offering sealed, spillproof protection and dependable starting power. If you're looking for a replacement battery that combines strong cranking capability with a long-lasting battery profile, the Mainstream MS9B replacement is crafted to meet those expectations.

Key Specifications

  • Model: MS9B (replacement for Mainstream MS9B)
  • Brand: SigmasTek
  • Voltage: 12 Volts
  • Amp-Hours: 8 AH
  • Terminal Type: Nut & Bolt
  • Design: Maintenance-Free Design
  • Technology: Absorbed Glass Mat Design (AGM Maintenance Free)
  • Safety: Spillproof and Leakproof Design
  • Certifications: U.L. Recognized and CE Certified
  • Valve System: Valve Regulated Vent System
  • Durability: Extreme Freeze, Heat and Vibration Resistance
  • Performance: Superior Starting Power and Deep Cycle Capacity
  • Condition: Brand New, Factory Fresh
  • Warranty: 6 Month Warranty

Benefits

The Mainstream MS9B replacement battery is built to withstand the rigors of daily use and extreme conditions. The AGM maintenance-free construction delivers a sealed, safe battery that resists leaks and tolerates shocks and vibration—ideal for motorcycle environments. As a high-performance battery, it provides the strong bursts of power needed for reliable engine starts and supports accessory loads with solid deep cycle capability.

With U.L. recognition and CE certification, this replacement battery meets important safety and quality benchmarks, contributing to a long-lasting battery life and trusted overall performance. Typical applications extend beyond motorcycles to include scooters, small power sport vehicles, emergency power packs, compact UPS systems, and portable tools demanding short, high-current discharges.

Choosing the Mainstream MS9B replacement means choosing reduced maintenance and improved dependability. Its valve-regulated vent system and factory-fresh condition ensure consistent, ready-to-use performance—giving you peace of mind whether you're commuting, touring, or storing your bike.

Upgrade now to a reliable replacement battery. Buy the Mainstream MS9B high-performance battery today for dependable starts, long service life, and fast shipment. Order now to secure your motorcycle’s power.


Payment & Security

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