Welcome to ECF, AMG...
The problem with "store brand" personal vaporizer products and new vapists... is that they purposely avoid telling you specifics about their products, and that actually they are the common products that most everyone sells. Without this knowledge, you feel a bit trapped into buying the same product from the same supplier... sort of a forced brand loyalty.
These products are often made by a Chinese manufacturer/distributor at the lowest possible wholesale price, and resold to you, the unsuspecting new vapist as top shelf, premium products... with a substantial profit margin to the retailer.
What you have is a very basic eGo/510 threaded battery and matching eGo threaded, plastic tank clearomizer with a net resistance of 1.8Ω... with this -
Ω - being the symbol for "Ohms". Ohm's being the standard value representing the electrical resistance of the coil wires used in the replaceable coil head assembly.
The resistance value, for your purposes, represents how much "power" will be required to energize the coil wires that heat and vaporize your e-liquid. Low power battery devices will make the most of resistance values 1.8Ω or higher... while inversely, lower resistance values will require higher current outputs.
All you need is an eGo threaded clearomizer, made by well respected companies like
Kanger,
Innokin or
Aspire... along with matching replacement coil head assemblies.
I would agree with edyle... if you intend to delve into the mechanics and basic electrical theory knowledge required to be a successful rebuilder/advanced vapist.
If that's not the case, and you prefer the simplicity of the devices you have, then look at the links I've provided and purchase name brand clearomizers, batteries etc etc... that are similar to your current equipment.