Skip to content
How to Recharge 18650 Batteries | Fogstar

How to Recharge 18650 Batteries

Do you remember the stone ages? When batteries once harvested of all their energy were rendered a lifeless, useless mass, their sole purpose now to infuriate the fool who finds it in the bottom of a drawer, optimistically hopeful that it may have life in it yet, before throwing it back in the drawer to repeat the same process six months later? Barbaric times. 

As we move closer and closer to a futuristic utopia, batteries replace matches and lighters as the unchallenged commodity for the modern day smoker (or vaper). As such, we recognise that someone needs to teach the children (and prevent our valued customers from battery explosions) about the science behind battery chargers. 

How do batteries work? 

Ordinary batteries are not designed for reuse, let’s get that out there right away. It is never a good idea to try and recharge standard batteries - we know at least one of you will try it anyway, but at least we can sleep tonight knowing we told you so! 

With normal batteries, once you turn on your remote, or torch (Imagine for a second, if you will, that you live in a world before torches were on your phone) you’re kickstarting chemical reactions inside the battery. As the current flows, the power-generating compartments inside the battery convert themselves from stored chemical energy into electrical power. Once the electrolyte has been fully converted, the battery dies, may it rest in power! 

How do battery chargers work? 

Rechargeable batteries, on the other hand, are tiny little frankensteins, who can be reanimated by the use of a battery charger! The charger makes the chemical reactions run in reverse, converting direct current from say, a wall socket, into alternating current inside the battery effectively resetting the battery chemicals.


Whilst theoretically, rechargeable batteries can be used indefinitely, they will degrade over time until there comes a time where they’re no longer willing to store charge. This is when they can be recycled (which is absolutely a euphemism for throwing in a bottom drawer and forgetting about them). 

A note about safety 

The cheapest battery chargers use a constant current or voltage and apply that to the batteries, until you turn the charger off. This means that if a charger is not turned off after a battery has fully recharged, the excess energy needs to find a way to escape - usually done by the battery heating up, building pressure. Batteries have been known to rupture, leak chemicals or even explode from time to time if left to overcharge too often. Whilst it’s improbable that your batteries will explode, it is worth noting it’s not impossible! All battery chargers should come equipped with safety features such as Reverse Polarity, Overcharge, Thermal Protection and Short Circuit - we’d advise that you buy your battery charger from a reputable, quality brand, y’know - on the off chance your batteries blow up! 

So, just a quick recap about battery charging; 

  1. Don’t try to charge standard batteries! 
  2. The current flowing from a wall socket to a battery, converts stored energy into electrical power. 
  3. When the stored energy is used up, the battery dies (RIP!) 
  4. A battery charger converts direct current from wall socket into alternating current inside the battery - recharging the battery. 
  5. Even rechargeable batteries will eventually lose the ability to store charge, nothing and no one lives forever folks! 
  6. Batteries that are left to overcharge do have the capacity to spontaneously explode, do not charge your batteries overnight! 
  7. Don’t try to charge standard batteries! 
If you’re looking for a trusted provider of superb 18650, 20700 or 21700 batteries, contact our specialists at Fogstar today on to discuss how we can help!
Previous article Are vaping devices allowed on planes?
Next article Can vape batteries be recycled?

Leave a comment

Comments must be approved before appearing

* Required fields