How many spare POC batteries can I bring on a plane?

For batteries under 100 Wh (which covers most Inogen and OxyGo single and double batteries), the FAA sets no numerical limit—but you must be able to physically carry them. Use the 150% rule based on your total transit time to determine the exact number you need.

Can POC batteries go in checked luggage?

No. All spare lithium-ion batteries must be in your carry-on baggage. Only the battery currently installed in the device may be in checked luggage (inside the device). This rule is non-negotiable under FAA Advisory Circular AC 120-76E.

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EB-BG991ABY BATTERY COMPATIBLE FOR SAMSUNG GALAXY S21 5G 4000mAH

$23.99

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The Genuine EB-BG991ABY Battery is the perfect replacement for your Samsung Galaxy S21 5G (SM-G991 series). With a 4000mAh high-capacity lithium-ion cell, this battery delivers reliable and long-lasting performance, ensuring your smartphone stays powered throughout the day.

This battery is brand new, genuine quality, and fully tested for safety. It is 100% compatible with the original Samsung Galaxy S21 5G battery and provides stable power for daily use, gaming, and multitasking.

If your phone suffers from fast battery drain, random shutdowns, or reduced battery life, replacing it with the EB-BG991ABY will restore your Galaxy S21 5G to optimal performance.

Key Features

Model: EB-BG991ABY
Compatible with: Samsung Galaxy S21 5G (SM-G991U, SM-G991B, SM-G991N, etc.)
Battery Type: Rechargeable Li-ion
Capacity: 4000mAh (high capacity, long-lasting)
Voltage: 3.85V
Condition: Genuine / 100% brand new
Safety Protection: Overcharge, over-discharge, overheating, and short-circuit protection
Performance: Stable, efficient, and durable power supply

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The batteries we sell are all brand-new ones. We do not offer refurbished or used batteries.Quality is king, and integrity is the foundation.
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Detail

FAQ

The Genuine EB-BG991ABY Battery is the perfect replacement for your Samsung Galaxy S21 5G (SM-G991 series). With a 4000mAh high-capacity lithium-ion cell, this battery delivers reliable and long-lasting performance, ensuring your smartphone stays powered throughout the day.

This battery is brand new, genuine quality, and fully tested for safety. It is 100% compatible with the original Samsung Galaxy S21 5G battery and provides stable power for daily use, gaming, and multitasking.

If your phone suffers from fast battery drain, random shutdowns, or reduced battery life, replacing it with the EB-BG991ABY will restore your Galaxy S21 5G to optimal performance.

Key Features

Model: EB-BG991ABY
Compatible with: Samsung Galaxy S21 5G (SM-G991U, SM-G991B, SM-G991N, etc.)
Battery Type: Rechargeable Li-ion
Capacity: 4000mAh (high capacity, long-lasting)
Voltage: 3.85V
Condition: Genuine / 100% brand new
Safety Protection: Overcharge, over-discharge, overheating, and short-circuit protection
Performance: Stable, efficient, and durable power supply

Battery Capacity	4000mAh/15.52Wh
Voltage	4.43V
Model No	EB-BG991ABY
Warranty	12 Months

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🔋 Lithium-Ion Battery Conditioning

For optimal electrochemical performance, new lithium-ion batteries should undergo 2–3 complete charge and discharge cycles before reaching full capacity.

This stabilization phase allows the internal cell chemistry to achieve balanced ion distribution, ensuring maximum runtime, stable voltage output, and extended cycle life.

After this initial conditioning period, no further full discharge cycles are required.

✅ Quality Issue – Free Return & Replacement

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12-Month Limited Manufacturer Warranty
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Replacement for defective or misrepresented items
Dedicated customer service response within 24 hours

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Orders placed Monday–Friday are processed within 1–2 business days. Orders placed on weekends are processed the following Monday.
Tracking information appears in your order within 1–2 business days after dispatch.
Transit time varies by region and logistics carrier
Please verify your shipping address before order confirmation
Address changes are not possible once shipment is dispatched

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US Shipping: USPS. (Normally 2-7 Business Days)

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We are committed to delivering professional-grade battery solutions and responsive after-sales service. If you experience any issues, please contact our support team before leaving feedback.

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✓ Safety & Quality Assurance

Built-in protection against overcharging, overheating, and short circuits.
Shipped in compliance with IATA regulations for lithium batteries.
Compatible with OEM chargers. No firmware modification required.

Questions about compatibility? Contact us with your device model number before ordering.

CC

Cao Chuanping

Power Systems Consultant · 8+ years in replacement battery sourcing & evaluation · View profile →

Disclaimer:
All batteries sold on accessories-mall.com are replacement parts. accessories-mall.com doesn't affiliate with any of the original manufacturers. Any registered trademarks or model names listed above are identified as purposes of showing compatibility only.

Samsung Galaxy S21 5G Genuine EB-BG991ABY Battery FAQ

Q1: Which devices is this battery compatible with?

A1: The EB-BG991ABY battery is specifically designed for the Samsung Galaxy S21 5G (SM-G991 series). It is not compatible with Galaxy S21 Plus, S21 Ultra, or other Samsung models.

Q2: What is the battery capacity?

A2: The EB-BG991ABY is a 4000mAh lithium-ion battery, providing long-lasting power and performance for the Samsung Galaxy S21 5G.

Q3: Is this an original Samsung battery?

A3: Yes. This is a genuine Samsung EB-BG991ABY battery, manufactured to the same standards as the original battery pre-installed in the Galaxy S21 5G.

Q4: How long does the battery last per charge?

A4: Under normal conditions, the 4000mAh battery supports a full day of usage, including calls, apps, internet, and standby. Battery life depends on individual usage and settings.

Q5: Can I replace the Galaxy S21 battery myself?

A5: The Galaxy S21 5G has a non-removable battery design, so replacement requires careful disassembly with the proper tools. If you are not experienced, professional installation is recommended.

Q6: Does this battery support Samsung fast charging?

A6: Yes. The genuine EB-BG991ABY battery supports Samsung Adaptive Fast Charging and is fully compatible with official wired and wireless chargers.

Q7: How many charge cycles can this battery handle?

A7: With proper care, the EB-BG991ABY battery lasts 300–500 full charge cycles, which typically equals 2–3 years of normal use.

Q8: Does the battery include safety protections?

A8: Yes. It comes with overcharge, over-discharge, overheating, and short-circuit protection, ensuring safe and reliable performance.

Q9: How should I store the battery if I’m not using it?

A9: Store the battery at 40%–60% charge in a cool, dry place. Avoid extreme temperatures and humidity.

Q10: How should I dispose of the old Galaxy S21 battery?

A10: Dispose of old batteries responsibly through a certified e-waste recycling facility. Do not burn, puncture, or throw in household trash.

EB-BG991ABY BATTERY COMPATIBLE FOR SAMSUNG GALAXY S21 5G 4000mAH