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SigmasTek  |  SKU: BW-7245

Scag Power Equipment STH-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 STH-18KH Lawn Mower

➤ 100% compatible with original Scag Power Equipment STH-18KH model

➤ Absorbent Glass Mat (AGM) technology for enhanced durability and performance

➤ Valve regulated, spill-proof design ensures safe and maintenance-free use

➤ Backed by a 1-year warranty for reliable, long-lasting power


📦🚀 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 STH-18KH Lawn Mower Battery (STH-18KH Compatible)

Specifically built to match the Scag Power Equipment STH-18KH lawn mower requirements, this brand new replacement battery offers dependable compatibility, consistent power delivery, and rugged reliability. If your STH-18KH needs a replacement, this factory-fresh battery delivers the deep cycle capability and maintenance-free performance required for heavy yard work and frequent starts.

Key Specifications

  • Compatible Model: Scag Power Equipment STH-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: Power/Volume Ratio Yielding 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 a long-lasting battery life and dependable starting power for the STH-18KH. AGM construction provides superior resistance to vibration and shock—important for lawn mowers that operate over uneven terrain—and is maintenance-free so you don’t have to top off fluid or perform routine service. The deep cycle design supports repeated discharge and recharge cycles, making this a practical, high-performance battery choice for seasonal and professional use.

Safety and reliability are reinforced by valve-regulated, spill-proof construction and recognized certifications (U.L. and CE). The battery’s high energy density yields more usable power relative to its size, enabling compact installation without sacrificing output. Typical applications include primary starting for lawn tractors, reserve power for lights and controls, and backup power for small equipment and accessories that depend on a stable 12V supply.

Because the STH-18KH requires the SP12-35 NB battery and uses the existing nut & bolt hardware, replacement is straightforward—swap in the new unit and restore reliable performance quickly. Backed by a 1 year warranty and a performance guarantee, this replacement battery is a smart, cost-effective choice when you need a dependable, long-lasting battery for your mower.

Restore dependable power to your Scag Power Equipment STH-18KH today—order this replacement battery now for fast shipping and reliable service. Buy with confidence and get back to mowing with a high-performance battery you can trust.


Payment & Security

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