Aspire K2 Vape Battery

An 800mAh replacement battery for Aspire's slim pen-style K2 kit. If your original K2 battery has started losing charge halfway through the day or refusing to fire consistently, this is the part you need, not a whole new kit. The 510 connection at the top fits the K2 tank directly, but it will also pair with most other 510-threaded tanks in a similar resistance range. 

Single-button operation, Micro-USB charging, carbon fibre-coated tube, and built-in safety protection across the board. Compact at 84mm x 15mm, it slips into a shirt pocket without adding bulk. Two colours available: Black and Pink. Over 18s only. Browse the full Aspire Range at Pirate Vapes.

Why vapers choose the K2 battery:

• Direct replacement for the original K2 kit battery, so you keep your existing tank and coils without buying a full starter kit again. That saves money and waste.

• 510 thread compatibility means it is not locked to the K2 tank alone. Most MTL tanks with coils in the 1.0ohm to 1.8ohm range will sit on this battery comfortably.

• Single button simplicity suits vapers who want zero learning curve: five clicks on, five clicks off, hold to fire. Nothing else to think about.

• Built-in triple safety protection covers overcharging, over-discharge, and short circuits. Peace of mind for a battery you carry in your pocket all day.

• 84mm x 15mm is about the length and width of a decent pen. Genuinely pocketable.

K2 Vape Battery Features

Fixed Output, Zero Guesswork

No variable wattage. No temperature control. The K2 battery delivers a consistent fixed voltage to whatever tank sits on top of it. For MTL vapers using BVC coils in the 1.2ohm to 1.8ohm range, that means a reliable, warm draw every single time without adjusting anything. Practically speaking, you press a button, and it works.

Why Carbon Fibre Coating Matters on a Pen Battery

The tube body has a carbon fibre finish that resists scratches and gives it some grip. Pen batteries live in pockets, bags, and on desks. The coating keeps it looking presentable after weeks of daily carry, which matters when the alternative is a scratched-up, peeling cylinder. Not glamorous, but functional.

LED Battery Indicator Saves You From Guessing

A small LED on the button changes colour based on remaining charge. Green means full. Red means charge it soon. Simple. You will not get caught on a commute with a dead battery if you glance at the light before you leave. Worth checking with your Chargers and Cables if your original Micro-USB lead has gone missing.

Three Layers of Safety Protection

Overcharge protection stops the battery from accepting more power than it can handle. Over-discharge protection shuts it down before the cell drains to a damaging level. Short circuit protection kills the power if something goes wrong with the connection. These three together mean you can charge it overnight without worrying, though Aspire recommends supervised charging as standard practice.

Sized for Actual Pockets

At 84mm long and 15mm wide, the K2 battery is smaller than most pens you would carry. It disappears into a jacket pocket, a trouser pocket, even a clutch bag. Paired with the slim K2 tank, the full setup weighs almost nothing. If you have moved away from bigger MTL Vape Kits because of size, this is the opposite end of the spectrum.

K2 Vape Battery Colours

Two options. Both use the same carbon fibre-coated body with a different finish.

• Black: Standard black. Understated, discreet, matches every tank colour you put on top of it.

• Pink: A lighter option that stands out. Same build quality and internals as the black.

How to Set Up the K2 Vape Battery

Quick and simple. Under a minute if your tank is already filled.

1. Charge the battery fully using the included Micro-USB cable. The LED will indicate a full charge. The first charge can take up to an hour.

2. Screw your 510 tank onto the top of the battery clockwise until snug. Do not overtighten. Finger-tight is enough to make a solid connection.

3. Press the fire button five times rapidly to power on the battery. The LED will flash to confirm.

4. Hold the button and inhale from your tank's mouthpiece. Release the button when you finish the draw.

5. Let a freshly filled tank sit for three to four minutes before firing if you have just installed a new coil. The cotton inside needs time to absorb the liquid fully. Firing on dry cotton permanently damages the coil.

6. Five rapid clicks again to lock the battery when you pocket it. Prevents accidental firing.

What's in the K2 Vape Battery Box

• The K2 battery unit in your chosen colour

• A Micro-USB charging cable. 

No tank, no coil, no e-liquid. This is a replacement battery only. If you need a full setup, the K2 Quick Start Kit includes the tank and a pre-installed BVC coil.

The MTL Battery for Aspire's Classic Pen Tanks

The K2 battery was designed for the K2 tank specifically, but the 510 thread means it physically fits any tank with a standard 510 connection. Thing is, the fixed output is optimised for coils in the 1.0ohm and above range. That means Aspire's BVC clearomiser coils, the Nautilus BVC coils at 1.6ohm or 1.8ohm, and similar MTL coils from other brands will all work well on this battery.

What it is not built for: sub-ohm tanks, DTL coils below 0.5ohm, or anything requiring variable wattage above 18W. The fixed output simply cannot drive those coils properly. If you need sub-ohm power, you need a different class of device entirely. Browse Vape Batteries for higher-powered options.

About Aspire

The K-series is where Aspire made its name with everyday vapers. The K1, K2, K3, and K4 each targeted a slightly different segment, but the K2 carved out a specific niche: a pen battery slim enough to carry anywhere, paired with a small-capacity MTL tank for vapers who wanted something that felt closer to a cigarette than a gadget.

Aspire built its early UK reputation on exactly this kind of hardware, straightforward devices that worked reliably without requiring technical knowledge. The K2 battery remains a genuine Aspire part for vapers still running that original setup.

Stock Up and Save

If your K2 battery is fading, chances are the coils could use a refresh too. Picking up a battery alongside a pack of BVC Replacement Coils covers both sides of the maintenance in one order.

Every order from Pirate Vapes ships same day before 4 pm in protective packaging. TPD-compliant stock, age-verified checkout, over-18s only. Spend over £25 and delivery is on us with Free Pirate Post.

Conclusion

The K2 battery is a no-nonsense replacement for Aspire's slim pen kit. 800mAh, fixed output, single button, 510 thread, and built-in safety protection. If your original battery has lost its edge, this swaps in without replacing anything else.

Two colours, Micro-USB charging, and a carbon fibre body that handles daily pocket carry. Browse more Vape Accessories and the full Aspire collection at Pirate Vapes.

FAQs

Does the K2 battery work with tanks other than the K2?

Yes. The 510 thread fits most standard tanks. Best suited to MTL coils at 1.0ohm and above. Not recommended for sub-ohm or DTL tanks.

How long does a full charge last in the K2?

Most MTL vapers get a full day from 800mAh with moderate use. Heavier vaping shortens that to half a day. Lighter users can stretch it further.

What charging cable does K2 use?

Micro-USB. One is included in the box. Any standard Micro-USB cable will work as a replacement.

Can I use sub-ohm coils with the K2 battery?

No. The fixed output is too low for coils below 0.5ohm. The battery cannot deliver the wattage those coils require, and the result would be poor vapour and flavour.

How do I know when the battery needs charging?

The LED indicator on the fire button changes colour. Green means charged. Red means low. When the light flashes rapidly during a draw, it is time to plug in.