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SigmasTek  |  SKU: BW-8538

Merits Pioneer 1 S143 High Performance Compatible Replacement Battery Set

Sale price $214.25 USD Regular price $280.53
Shipping calculated at checkout.

➤ Includes 2 high-performance 12V 35AH batteries with NB terminals

➤ Maintenance-free and spill-proof AGM technology for safety and reliability

➤ Designed for long service life and wide operating temperature range

➤ Guaranteed compatibility with original Merits Pioneer 1 S143 batteries

➤ Comes with a 1-year warranty and fast shipping within 1 business day


📦🚀 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

Merits Pioneer 1 S143 Replacement Battery - Compatible with Merits Pioneer 1 S143

Restore reliable power to your Merits Pioneer 1 S143 with this dedicated set of replacement batteries. Specifically compatible with the Merits Pioneer 1 S143, this package includes two 12V 35AH sealed batteries engineered for dependable performance, high-discharge capability, and consistent operation in varied temperatures. These high-performance batteries are designed to meet or exceed the original manufacturer specifications so you can rely on them for daily mobility needs and extended use.

Key Specifications

  • Package contains: 2 batteries
  • Volts: 12
  • Amps: 35 (35 AH)
  • Weight: 49.4 Lbs (as listed)
  • Length: 7.72 (inches)
  • Width: 5.14 (inches)
  • Height: 6.14 (inches)
  • Terminal: NB (Nut & Bolt)
  • Chemistry: SLA (Sealed Lead Acid)
  • AGM Technology: Yes
  • Maintenance-free: Yes
  • Spill Proof: Yes
  • Guaranteed compatibility with original batteries
  • Warranty: 1-year Warranty
  • Brand: SigmasTek
  • Shipping Methods: UPS Ground and USPS
  • Shipping Speed: We ship in 1 business day for all in-stock items

Benefits

  • Durability: AGM construction and spill-proof design keep the cells secure and require no routine maintenance, ideal for mobility devices like the Merits Pioneer 1 S143.
  • Long Life: Engineered for high discharge and wide temperature tolerance, these batteries are a long-lasting battery solution that reduces the need for frequent replacement.
  • High Performance: Provides consistent power delivery and stable voltage under load — a true high-performance battery choice to maintain operational reliability.
  • Installation Convenience: Replace using the same original configuration and cables; NB (Nut & Bolt) terminals match the factory connections for simple swap-in replacement.
  • Multiple Uses: While tailored for wheelchairs, these 12V 35AH SLA/AGM batteries also suit UPS backup, emergency power systems, and small DC tools where sealed lead-acid batteries are appropriate.
  • Reliable Support: Manufactured to meet or exceed OEM expectations and supported with a 1-year warranty and fast shipping to minimize downtime.

Don’t wait — order this pair of replacement batteries for your Merits Pioneer 1 S143 today to secure a high-performance, long-lasting battery solution. Fast shipping and a 1-year warranty make it easy to get back to reliable mobility.


Payment & Security

Payment methods

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