Samsung 35E 18650 Battery 3500mAh 8A - Flat Top (4-Pack) - Free Shipping

Key Features

• Exceptional Capacity: 3500mAh typical (3350mAh minimum) keeps your flashlights, headlamps, and portable fans running significantly longer between charges.

• Stable 8A Continuous Discharge: Supplies reliable current for mid-power applications up to 8 amps; ideal for regulated bike lights, and DIY power banks with moderate draw.

• Genuine Samsung Grade-A Cells: 100% authentic INR18650-35E produced by Samsung SDI, with original factory QC, zero-cycle freshness, and no rewraps or reclaimed cells.

• Long Cycle Life: Achieves ≥500 charge/discharge cycles (to 70% remaining capacity) under standard conditions, minimizing replacement frequency and total cost of ownership.

• Flat Top for Pack Building: Perfectly flat positive terminal simplifies series/parallel stacking and nickel strip spot-welding, ensuring low-contact-resistance assembly.

• High Energy Density: Approx. 250 Wh/kg; carry more energy without adding bulk or weight, essential for portable and wearable devices.

• Integrated Safety Mechanisms: Built-in CID (Current Interrupt Device), PTC thermistor, and vent disk offer multiple layers of passive protection under abusive conditions.

• No Memory Effect: Li-ion chemistry allows partial charging/discharging at any time without capacity loss, delivering maximum convenience.

• Free Shipping Included: The 4-pack ships for free, making it risk-free to try or restock. Fast processing and fully trackable delivery.

This is flat‑top| Needbutton‑top? Click here

Parameters

Applications

• Flashlights & Headlamps: Enjoy remarkably extended runtime on high-output 18650 torches, searchlights, and headlamps. Flat top fits most spring-loaded or dual-spring battery tubes.

• DIY Power Banks & USB Chargers: Combine these four cells inside a 1S4P power bank enclosure to create a massive 14,000mAh portable charger for camping, travel, or emergency preparedness.

• Power Tool Battery Rebuilds: Revive old cordless drill, impact driver, or handheld vacuum battery packs by spot-welding flat top 35E cells into the existing cluster with a compatible BMS.

• E-Bike / E-Scooter / Solar Storage: In 10S, 13S or other series configurations, the 35E cells serve as high-capacity energy storage for light electric vehicles, home solar banks, and UPS backups (professional assembly and balance BMS required).

• Solar Garden & Security Lights: Consistent discharge performance over a wide temperature range and long cycle life make them perfect for outdoor solar-recharged lighting.

• Medical & Industrial Devices: Stable voltage output suits portable monitors, infusion pumps, handheld meters, and data loggers that demand dependable, long-lasting power.

• RC Transmitters & Wireless Gadgets: Upgrade your radio controller battery bay or power wireless cameras, sensors, and robots with confidence.

• ⚠️ Compatibility Check: This is a Flat Top cell. If your device requires a Button Top (like some flashlights or mods with a recessed positive terminal), this battery will not work. Please check your device manual before ordering. (We also offer a Button Top version).

Assembly Warning: Never solder directly onto battery terminals. Pack assembly must be performed with a spot welder using pure nickel strips, and a matching Balance Management System (BMS) must be used for series connections. Unprotected cells must not be used in devices without integrated overcharge/over-discharge protection.

FAQ

1. Are these protected batteries? What’s the terminal type?
No, these are flat top unprotected cells without any built-in protection PCB. The positive terminal is flush with the battery can. They require an external protection circuit or should be used in devices that have built-in low-voltage/overcurrent safeguards.

2. Is the 3500mAh capacity real? What capacity can I expect in actual use?
Absolutely. The typical capacity is 3500mAh down to 2.65V under 0.2C load. Real-world devices usually cut off around 3.0V–3.2V, so usable capacity will be slightly less—often around 3300mAh–3400mAh—but still tops among high-capacity 18650s. Minimum capacity is guaranteed above 3350mAh.

3. Why flat top instead of button top?
Flat tops allow optimal contact when stacking cells in battery packs, especially for spot welding. They also fit snugly in flat-contact battery bays. If a device requires a button top, you may cautiously use a neodymium magnet spacer, but beware of the risk of short circuit if the magnet shifts.

4. What charger should I use?
Use a quality lithium-ion charger from brands like XTAR, Nitecore, Gyrfalcon, or Efest with CC/CV algorithm, accurate 4.2V termination, and reverse-polarity protection. Charge at 0.5C (1700mA) for best lifespan; occasional 1C (3350mA) is acceptable.

5. Are the 4 cells matched for capacity and internal resistance?
This pack provides cells from the same batch with consistent voltage, but does not include precision matching service. For series packs, a balancing BMS is strongly recommended. If you need closely matched cells for professional builds, please reach out to us for a custom matching quote.

6. Do I need to charge them upon arrival? How to store them?
Samsung ships cells at approximately 3.6V (40–50% state of charge), which is ideal for storage. You can use or store them immediately. For prolonged storage, keep them in a cool, dry place (around 20°C / 68°F) and top up to 3.6–3.7V every 6–12 months to prevent over-discharge.

7. How do I know these are authentic Samsung cells?
We guarantee authentic Samsung SDI INR18650-35E cells. Genuine cells feature crisp heat-shrink wrap printing, embossed ring on the positive cap, and a slightly raised, laser-etched model code. Counterfeit cells often have blurry text, absent vent features, or different weight. Full refund if proven otherwise.9. Can I solder wires directly to the battery?
Absolutely not! Soldering transfers dangerous heat into the cell, damaging the internal separator, safety vent, and seals, and can cause fire or explosion. Always use a capacitive spot welder with pure nickel strips for electrical connections.

8 What does “Free Shipping” include? When will I receive my order?
This 4-pack qualifies for free standard shipping with tracking. Orders are processed within 1–3 business days. Delivery typically takes 5–10 business days depending on your location. Expedited options may be available at checkout for an additional fee.

9. Can these batteries be taken on an airplane?
According to IATA regulations, lithium-ion batteries under 100Wh may generally be carried in carry-on baggage when properly protected against short circuits. Each Samsung 35E is approximately 12.6Wh (4 cells = 50.4Wh). However, airline policies vary; please verify with your carrier before flying. Always insulate terminals individually.

10. Will these fit my device with a flat top?
They fit most 18650 devices, but some hosts with physical reverse-polarity protection (a raised ring at the positive contact) may not make contact with a flat top. Check your device’s manual or inspect the positive terminal shape. A small magnet spacer can sometimes bridge the gap, but proceed carefully.