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SigmasTek  |  SKU: BW-7243

Scag Power Equipment STHM-18KH High Performance Lawn Mower Replacement Battery

Sale price $102.50 USD Regular price $135.64
Shipping calculated at checkout.

➤ Factory fresh replacement battery for Scag Power Equipment STHM-18KH Lawn Mower

➤ Uses advanced Absorbent Glass Mat (AGM) technology for durability

➤ Valve regulated, spill-proof design ensures safe operation

➤ High energy density delivers superior power and long life

➤ Comes with 1-year warranty and guaranteed performance


📦🚀 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 | 35 AH

Terminal Type

Nut & Bolt

Replacement Scag Power Equipment STHM-18KH Lawn Mower Battery (STHM-18KH Compatible)

This replacement battery is designed specifically for the Scag Power Equipment STHM-18KH lawn mower, delivering reliable compatibility, consistent performance, and the durability you need for demanding outdoor equipment. Built to OEM-equivalent standards, this factory-fresh battery offers the dependable power profile required by your STHM-18KH so you can start and operate your mower with confidence. If you need a high-quality replacement battery that balances safe, maintenance-free operation with deep cycle capability, this STHM-18KH replacement is an excellent choice.

Key Specifications

  • Compatible Model: Scag Power Equipment STHM-18KH
  • Required Battery Part: SP12-35 NB (12 V 35 AH)
  • Voltage: 12 Volts
  • Capacity: 35 AH (Amp-hours)
  • Terminal Type: Nut & Bolt
  • Battery Technology: Absorbent Glass Mat (AGM)
  • Cycle Type: Designed for Deep Cycle Usage
  • Construction: Valve Regulated Spill Proof
  • Energy Density: High power/volume ratio for unrivaled energy density
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Warranty: 1 Year Warranty
  • Performance: Performance Guaranteed

Benefits

This replacement battery delivers the long-lasting battery life and resilient performance expected for heavy-duty lawn and garden equipment. Using advanced AGM technology, it provides superior vibration resistance, reduced self-discharge, and maintenance-free operation—ideal for seasonal use and continuous service. Designed for deep cycle usage, the battery supports repeated charge/discharge cycles without rapid capacity loss, making it a dependable high-performance battery for start-up power and electrical accessories.

Durability is built into the valve regulated, spill-proof construction which keeps the battery safe in the rugged conditions typical to outdoor equipment. U.L. recognition and CE certification confirm compliance with safety and quality benchmarks, while the 1 year warranty and the manufacturer’s performance guarantee provide peace of mind. Typical applications include primary starting power for lawn mowers, reserve power for on-board electronics, and supportive power for accessories and attachments.

Because this is a true replacement battery matched to the STHM-18KH specification (SP12-35 NB), installation uses your existing cables and hardware—simply swap the old unit for this factory-fresh battery for immediate improvement in reliability and start-up performance. Whether you need dependable seasonal readiness or continuous everyday use, this high-performance battery is built to last.

Ready to upgrade? Purchase this replacement Scag Power Equipment STHM-18KH battery today and enjoy a long-lasting battery that restores dependable power to your mower. Order now to get fast shipping and reliable support.


Payment & Security

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