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CPLD-439 3900mAh 3.87V Li-ion Polymer replacement battery for Rakuten Big S, front view showing battery surface and small 2-pin connector

CPLD-439 3900mAh 3.87V Battery for Rakuten Big S 5G Replacement

Original price was: $33.99.Current price is: $28.99.

🔘 CPLD-439 3900mAh 3.87V | 🔋 Li-ion Polymer | 📱 For Rakuten Big S

8 in stock

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SKU: CPLD-439 Category: Tags: , , , ,
📦 Shipping, Warranty & After-Sales Information (Click to expand ▼)

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Warranty Period90 days from delivery15-30 days from order confirmation
When It Starts📦 Upon delivery⚠️ Upon order confirmation (even before you receive it)
Claims HandlingWe do it directly — email usAutomated dispute system, seller dependent
After Window ExpiresStill can contact us for supportNo recourse, seller can ignore you

🔋 90-day warranty is the industry standard for replacement batteries. Batteries naturally lose capacity over time — this normal wear is not covered. Warranty applies to manufacturing defects only.

📦 Shipping Cost & Delivery Time (Economy Shipping from China)

📦 Note: Batteries are classified as hazardous goods and must be shipped via specialized channels, which may take slightly longer than standard couriers. Delivery times are estimates and may be affected by customs, weather, or other unforeseen circumstances. If your country is not listed in the table below, we are currently unable to ship batteries to that destination.

DestinationFreight (USD)Est. Delivery Time
United States$7.808–15 days
Canada$6.8018–30 days
Mexico$10.0030–60 days
Germany, France, United Kingdom, Greece$6.5018–30 days
Austria, Belgium, Czech Republic, Denmark, Estonia, Hungary, Ireland, Italy, Luxembourg, Netherlands, Norway, Poland, Portugal, Slovakia, Spain, Sweden, Switzerland, Ukraine$8.0018–30 days
Croatia, Finland, Lithuania, Latvia, Slovenia$8.0030–50 days
Bulgaria, Romania$14.0030–50 days
South Korea, Japan, Australia, New Zealand, Israel, Malaysia, Singapore, Thailand, Philippines, Kazakhstan$7.5018–30 days
United Arab Emirates, Saudi Arabia, Vietnam, Chile, Peru, Colombia, Brazil$18.0025–60 days

🇧🇷 Note for Brazil: Brazilian customs can occasionally cause delays of up to 80 days or more. And please indicate the recipient's CPF, as it is required for Brazilian customs and shipping. Thanks! We appreciate your understanding.

🇪🇺 Note for EU countries: Due to new EU customs regulations effective July 1, 2026, a flat tariff fee of $4.00 (approx. €3.50) applies to shipments to EU countries. This fee covers customs tariff, handling, and payment processing costs, and will be added at checkout. Thank you for your understanding.

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Description

✅ Condition: New – Factory-tested quality & Warranty

✅ 3900mAh High Capacity – Restores full battery life for Rakuten Big S

✅ CE / RoHS / UN38.3 Certified

✅ 90-Day Warranty from delivery – Longer coverage than major platforms

✅ Ships in 3-7 days with tracking

🛡️ Shipping Protection Available at Checkout

✅ PayPal Buyer Protection included

✅ 100% Compatibility Guarantee – If it doesn’t fit, we’ll refund you. No questions asked.

⚠️ Low Stock Alert: Only 8 left in stock. Order now to avoid waiting.

Battery model: CPLD-439
Capacity: 3900mAh (typical) / 15.09Wh
Rated voltage: 3.87V
Charge limit voltage: 4.45V
Battery type: Li-ion Polymer (Grade A cells)
Compatible with: Rakuten Big S
Package include: 1 x battery
Restore the reliable battery performance of your Rakuten Big S with this CPLD-439 3900mAh replacement battery. The Rakuten Big S features a 6.4-inch OLED display with HDR10 support, powered by the Qualcomm Snapdragon 765G 5G mobile platform with 6GB RAM. After 1-2 years of regular charging cycles, the original battery’s capacity naturally declines. This Li-ion Polymer battery restores the full 3900mAh capacity, bringing back the consistent daily endurance your device was built for. Built with Grade A cells and multi-layer safety protection against overcharge, over-discharge, and short circuits. CE, RoHS, and UN38.3 certified.
Designed for Reliable Daily Use: The 3900mAh battery in the Rakuten Big S originally provided dependable endurance for 5G connectivity, streaming on the OLED display, photography with the 48MP quad-camera system, and daily tasks. After years of charging cycles, battery capacity degrades significantly. Common symptoms include: the device requiring more frequent charging than when new, unexpected shutdowns at 15-20% battery remaining, slower charging than when new, or visible battery swelling. This replacement restores the original endurance, allowing you to continue using your Rakuten Big S without interruption. The CPLD-439 battery uses advanced high-density cell technology with multi-layer safety protection, ensuring reliable performance for years to come.
Compatibility Note: Fits Rakuten Big S only. Please confirm your battery model before ordering — CPLD-439 is printed on your original battery. This battery is NOT compatible with Rakuten Big, Rakuten Mini, or other Rakuten models. The Rakuten Big S uses a specific 3900mAh battery with precise dimensions; using a different battery model may cause improper fit, charging issues, or incorrect battery reporting.

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Frequently Asked Questions

The CPLD-439 battery for Rakuten Big S is compatible with Rakuten Big S only. If you need a Rakuten Big S battery replacement, this CPLD-439 3900mAh battery is the exact match. For CPLD-439 battery for Rakuten Big S compatibility, please verify your device model in Settings > About Phone or check the label on your original battery — the model number CPLD-439 is printed there. The Rakuten Big S features a 6.4-inch OLED display and Snapdragon 765G processor. This battery is NOT compatible with Rakuten Big, Rakuten Mini, or other Rakuten models. If your Rakuten Big S battery no longer holds charge as it did when new or shuts down unexpectedly, this CPLD-439 replacement battery will restore the full performance.

The CPLD-439 3900mAh battery for Rakuten Big S has a typical capacity of 3900mAh (15.09Wh) and a rated voltage of 3.87V, with a charge limit of 4.45V. This CPLD-439 3.87V 3900mAh Li-ion Polymer battery is built with Grade A cells and is CE, RoHS, and UN38.3 certified. For best performance, allow 2-3 full charge cycles after installation to calibrate the battery meter. If your original battery now requires more frequent charging than when new, this replacement will restore the original capacity.

Professional Rakuten Big S battery installation is recommended. The Rakuten Big S has a sealed design with an internal battery. To replace Rakuten Big S battery CPLD-439, the technician must heat the back cover to soften adhesive, carefully pry it open to avoid damaging the OLED display or frame, disconnect the battery's small 2-pin connector, remove the old battery, and install the new CPLD-439 battery before resealing the device. For CPLD-439 battery installation Rakuten Big S, improper handling can damage the display or compromise the device's water resistance. Authorized service centers are recommended. For Rakuten Big S battery health maintenance: 1) Use the original charger and cable for optimal charging. 2) Keep battery level between 20% and 80% for daily use to maximize the lifespan of the 3900mAh cell. 3) Avoid exposing the device to high temperatures (above 40°C / 104°F), especially while charging. 4) For long-term storage (over 2 months), keep the battery at approximately 40-60% charge. 5) Perform a full calibration cycle after installation: drain the device until it auto-shuts off, then charge uninterrupted to 100%. For Rakuten Big S battery care tips, stop using immediately if the battery shows any swelling.

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