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.

11.1V vs. 11.4V? The Ultimate Guide to Laptop Battery Voltage Compatibility

March 16, 2026 Cao Chuanping

You flip your laptop over, the original battery says 11.1V, but the replacement you found online says 10.8V or 11.4V. Does it matter? Will it fry the motherboard? The short answer: those three numbers almost always describe the same kind of pack — and here's exactly why, plus the one jump you must never make.

The number that actually matters: cell count, not the decimal

A laptop battery is several lithium-ion cells wired in series. Each cell has a nominal voltage of roughly 3.6 to 3.8V, and the pack's rated voltage is simply that figure multiplied by the number of cells in series. So the headline voltage is really telling you the series cell count — and that's what compatibility hinges on.

3.7V+ 3.7V+ 3.7V= 11.1V (3S)

3.8V+ 3.8V+ 3.8V= 11.4V (3S)

Same three cells in series. The only difference is cell generation: older cells are rated 3.7V, newer high-voltage cells 3.8V. 10.8V is the same 3-cell pack rounded conservatively (3 x 3.6V).

This is the key correction to a myth you'll see repeated online: 11.4V is not a "4-cell" battery, and the difference between 11.1V and 11.4V is not an extra cell. They're both 3-cell (3S) packs. The 0.3V gap is just newer cell chemistry with a slightly higher nominal voltage and charge ceiling — the laptop's charging circuit is designed to handle that small range.

So which voltages are interchangeable?

Group batteries by series count. Within the same group, a quality pack is generally a safe swap (assuming the connector, shape, and capacity also match). Across groups, never.

Common 3-cell vs 4-cell laptop battery voltages.
Rated voltage	Series config	What it really is	Swaps with
`10.8V`	3S	3 x 3.6V (older)	10.8 / 11.1 / 11.4V
`11.1V`	3S	3 x 3.7V (common)	10.8 / 11.1 / 11.4V
`11.4V`	3S	3 x 3.8V (newer)	10.8 / 11.1 / 11.4V
`14.4V`	4S	4 x 3.6V	14.4 / 14.8V only
`14.8V`	4S	4 x 3.7V	14.4 / 14.8V only
`15.2V`	4S	4 x 3.8V	15.2 / 14.8V (verify)

The practical takeaway: 10.8V, 11.1V, and 11.4V are three labels for the same 3-cell family and are normally interchangeable. So are 14.4V and 14.8V within the 4-cell family. The replacement's small decimal difference is expected, not a defect.

The one line you must never cross: don't move between the 3-cell group (≈10.8–11.4V) and the 4-cell group (≈14.4–15.2V). Putting a 14.8V pack into an 11.1V slot is a different series count and a much higher voltage — that's where real charging-circuit damage happens.

How to find your correct voltage in 30 seconds

Read the original battery label. Voltage is printed right next to capacity (Wh / mAh) and the part number — this is the authoritative source.
Match the part number, not just the voltage. The P/N guarantees the connector and shape fit too, which voltage alone doesn't.
Check capacity (Wh). You can go equal or slightly higher for more runtime; don't go lower. Higher Wh at the same voltage just means longer battery life.
Confirm the connector and physical shape. Same voltage with the wrong connector still won't fit.

Not sure how to read your label or find the part number? Our part-number identification guide walks through every step.

Signs you're holding the wrong (or a failing) battery

Whether from a mismatch or a low-quality cell, watch for rapid drain, overheating, physical swelling, or a pack that won't charge or isn't detected. Any of these means stop using it and replace it with a correctly specified pack. A swollen battery in particular should be removed from service promptly.

Where we fit in

We're an independent supplier of OEM-grade replacement batteries — not a laptop manufacturer. Every pack we list specifies its exact voltage, capacity, connector, and the part numbers it replaces, so you can match the 3-cell or 4-cell group correctly the first time. Send us your battery's part number and we'll confirm the fit before you order.

Ready to find the right pack? Browse our laptop battery collection, or message your part number on WhatsApp and we'll verify voltage and connector compatibility for you.

Frequently asked questions

Can I replace an 11.1V battery with an 11.4V one?

Usually yes — both are 3-cell packs (11.1V = older 3.7V cells, 11.4V = newer 3.8V cells). A quality 11.4V pack is a safe modern replacement for an 11.1V slot if connector, shape, and capacity match. Confirm via the part number.

Are 10.8V and 11.1V the same?

Effectively yes — both label the same 3-cell pack (10.8V = 3 x 3.6V, 11.1V = 3 x 3.7V). You'll see the two used interchangeably for one physical battery.

Can I use a 14.8V battery if my old one was 11.1V?

No. 14.8V is a 4-cell pack, 11.1V is 3-cell — different series count and much higher voltage. It can damage the charging circuit. Never cross between 3-cell and 4-cell.

Will a third-party battery void my warranty?

Often not, if it's the correct voltage with a proper protection circuit — but rules vary by manufacturer and country. Check your terms and choose a certified (CE/RoHS/UL) pack that matches your spec.

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