Cartridge: 510 batteries
What they are, and what the number means
If your prescription came as a cartridge rather than dried flower, you will have been told you need a "510 battery" and possibly nothing else. It is one of those terms that everyone uses and nobody explains.
What it actually is
A 510 battery is a power source. That is all it is.
Your cartridge — the part that came from the pharmacy, containing your medication — has a small heating element inside it. It has no power of its own. The battery screws onto the bottom, supplies electricity to that element, and the element warms the oil enough to turn it to vapour.
So the cartridge is the medicine and the clever part. The battery is a rechargeable handle that supplies electricity to it. That division matters, because it explains the two things people find confusing: why the battery is bought separately, and why it is not regulated as a medical product. The cartridge is a prescription item. The battery is a piece of consumer electronics, and anyone may sell it.
What "510" means
510 is a thread size — the screw fitting where the cartridge meets the battery.
It became the common size across the industry years ago, and it stuck. It is a de facto standard rather than an official one: no regulator defines it, manufacturers simply converged on it. In practice that convergence is what matters to you — any 510 cartridge will physically fit any 510 battery.
You may see the number explained as a reference to the dimensions of the thread. That explanation is repeated widely, but we have not been able to trace it to a primary source, so treat it as folklore rather than fact. It has no bearing on anything practical.
A setting that matters: voltage
If a 510 battery has any adjustment at all, it will be voltage — sometimes shown as a number in volts, sometimes as colours or heat levels.
Voltage controls how hard the battery drives the heating element, which controls how hot the oil gets. This is the difference between a good experience and a wasted cartridge:
Too low and very little happens. Thin or no vapour, and it can feel like the cartridge is faulty when it is not.
Too high and you overheat the oil. That produces a harsh, burnt taste, and it can damage the cartridge — in some cases permanently, after a single use. It also gets through your prescription faster than you intended.
Cartridges from UK pharmacies are generally designed to work in a modest voltage range. The practical advice is straightforward: start at the lowest setting and work up only if you need to. If a battery offers a setting far above what your cartridge is designed for, that setting is not a feature, and using it is the most common way people ruin a cartridge.
The features you will see; whether they matter
Draw-activated or button. Draw-activated batteries switch on when you inhale, with no button at all. Button batteries need you to hold a button while you inhale. Draw-activated is simpler; a button gives more control and is harder to trigger by accident in a bag or pocket.
Variable voltage. Worth having. Different cartridges suit different settings, and a fixed-voltage battery gives you no way to adapt if the next one behaves differently.
Preheat. A short, gentle warm-up cycle. Genuinely useful in cold weather or with thicker oils, which get sluggish and can be hard to draw through when cold.
USB-C charging. Worth insisting on. Older micro-USB fittings wear out, and a battery you cannot charge is a battery you cannot use.
App connectivity, screens, ornamentation. Rarely worth paying for on a battery.
When something goes wrong
Burnt taste. Almost always voltage set too high. Turn it down. If the taste persists at the lowest setting the cartridge element may already be damaged.
No vapour, battery clearly working. The cartridge may be cold, or the oil may have settled. A preheat cycle usually resolves it.
Nothing at all. Check the cartridge is screwed in firmly but not overtightened — overtightening is a common cause and can damage the connection at both ends.
Leaking. Store it upright, and avoid leaving it in a hot car or a sunny windowsill. Heat thins the oil and it finds its way out.
What we stock, and why
We stock CCELL batteries. The reason is compatibility rather than brand preference: CCELL make the internal heating hardware used inside a great many licensed producers' cartridges, so matching the battery to the same manufacturer's standard removes a variable.
We do not stock the high-output batteries sold for other purposes. They will fit — everything 510 fits — but they run at voltages your cartridge was never designed for, and the fit is the only thing they have going for them.
General information, not medical advice
As Prescribed sells equipment. We are not a pharmacy, a clinic or a prescriber, and nothing here is medical advice. This article is general information written for people who already hold a prescription — it is not tailored to you and takes no account of your condition, your other medicines or your circumstances.
Please read things for yourself: follow the manufacturer's instructions supplied with your device and the patient information supplied with your medication in preference to anything we have written. For anything about your medication, your dose or your condition, speak to your prescribing clinician or your dispensing pharmacy.
We set out what we know so you can weigh it up, check it against your own sources, and decide for yourself what suits you.
