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.

Cracking the BIOS Error: Why Your Laptop Can’t Recognize Its New Battery (And How to Fix It)

May 8, 2026 Cao Chuanping

You did everything right — checked the model, ordered the battery, installed it carefully. Then you power on and get a black screen with "Primary Battery Not Recognized," or Windows shows "Plugged in, not charging." Is the new battery dead on arrival? Almost never. In most cases the cells are perfectly fine, and the problem is a failed conversation between your laptop and the battery.

The short version

This is a firmware handshake issue, not a dead battery. When a pack is installed, your laptop's embedded controller and the battery's BMS exchange identity and status data. If that exchange doesn't complete, the laptop refuses to charge a battery it can't verify. The good news: most cases clear with a simple reset — no new battery needed.

What's actually happening

Your laptop doesn't just draw power from a battery; it talks to it. Inside every modern pack is a small management board (the BMS) that reports the battery's identity, voltage, temperature, and charge state. The laptop's firmware (BIOS/UEFI plus the embedded controller) checks that data before it agrees to charge.

Laptop firmwareBIOS / EC

⇄

Battery BMSidentity + status

Charginghandshake OK

When that handshake fails — because of a stale BIOS, a charge-limit setting, a temporary controller glitch, or a pack whose identity didn't verify — the laptop falls back to a safe state: it runs on AC and shows "not charging." So before you blame the battery, it's worth walking the fixes from easiest to most involved. Most people are sorted by step two.

The fix, easiest first

Power-drain reset 2 minutes

This clears a stuck embedded controller and resolves a surprising share of cases. Shut down fully, unplug the charger, and remove the battery if it's removable. Then hold the power button for 30 seconds to drain residual charge. Reconnect the battery and charger and power on.
Check for a charge-limit setting 2 minutes

If you ever enabled a conservation / charge-threshold mode (cap at 60–80%) and the new battery shipped above that level, the laptop says "Plugged in, not charging" on purpose. Open your maker's app (Lenovo Vantage, Dell Power Manager, MyASUS, etc.) and confirm the limit isn't the cause.
Reseat the battery 5 minutes

A connector that's a hair off won't handshake. Power down, reopen, unseat the battery and its connector, and firmly reseat both. Confirm there's no debris on the contacts.
Reset BIOS to defaults moderate

Enter BIOS/UEFI setup (usually F2, F10, or Del at boot) and load optimized/factory defaults. This clears a misconfiguration that can block recognition. Save and exit.
Update the BIOS moderate

An older BIOS may simply not know how to talk to a newer or third-party pack. Download the latest BIOS from your manufacturer's support page for your exact model and apply it on AC power, fully charged or with a working battery — never let it lose power mid-flash.
Run the maker's battery diagnostic moderate

Built-in tools report whether the laptop sees a valid pack: Dell SupportAssist, HP Support Assistant, Lenovo Vantage. They'll often tell you directly whether it's a handshake/recognition issue or a real fault.
Confirm the part is correct — and genuinely good last resort

If nothing above works, verify the pack truly matches: part number, voltage, and connector. A mismatched part number or a low-grade pack with the wrong BMS can fail the handshake by design. A correctly specified, quality battery completes it just like an original.

One caution on BIOS flashing: never interrupt a BIOS update. A failed flash can brick the motherboard, which is far worse than a charging error. If you're not comfortable, stop at the diagnostic step and get professional help.

Quick diagnosis: which cause is it?

Match your symptom to the most likely fix.
Clue	Likely cause	Go to
Error appeared right after install, battery is correct part	Controller glitch	Step 1 (drain reset)
"Not charging" but battery is at 70–80%+	Charge-limit setting	Step 2
Laptop is several years old, never BIOS-updated	Stale BIOS	Step 5 (BIOS update)
Works intermittently, or only when pressed	Loose connector	Step 3 (reseat)
Pack was very cheap / unbranded	Wrong or missing BMS	Step 7 (verify part)

How to avoid this next time

Most recognition errors trace back to a part mismatch or a low-grade BMS, so the prevention is simple: buy by exact part number (not just "fits Dell"), keep your BIOS reasonably current, and choose a pack whose BMS is built to your laptop's spec so it handshakes cleanly the first time. Our guide to cell grades and BMS quality covers why that matters, and the voltage compatibility guide helps you match the spec.

Not sure your pack is the right one? Send us your laptop model and the part number on the battery label via WhatsApp and we'll confirm the exact match before you order — every battery we ship is built to handshake correctly so your laptop recognizes it without errors. Browse the laptop battery collection.

Frequently asked questions

Is my new battery dead on arrival if it isn't recognized?

Usually not. Most cases are a firmware handshake between the laptop's controller and the battery's BMS. A power-drain reset and reseat fix a large share before the battery is ever at fault.

Why does it say "Plugged in, not charging"?

The laptop sees a battery but chose not to charge it — often a failed handshake, a charge-limit setting, or an identity that didn't verify. Typically a settings/handshake issue, not a dead pack.

Will a third-party battery always cause this?

No. A correctly matched pack with a proper BMS handshakes like an original. The error is more common with a wrong part number, the wrong BMS, or an outdated BIOS — not with all aftermarket batteries.

Could a charge-limit setting be the cause?

Yes. If a conservation/threshold mode caps at 60–80% and the battery is already above that, "Plugged in, not charging" is intentional. Check that first.

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