has this listed online. Protected batteries are quite often longer in length than their unprotected counterpart. This is due to the additional circuitry that is embedded in the battery. You should confirm measurements before you commit to purchasing. Now, this said, lithium ion batteries have what’s called a PTC or Positive Temperature Coefficient circuit. This is built into the battery just above the positive terminal and is present regardless of any “protected” labels. The PTC is designed to raise the resistance of the battery as the temperature of the battery rises. The theory behind PTC is that as the resistance goes up, the current draw from the battery goes down, ohms law. This helps prevent most accidents from becoming catastrophic, but it should not be relied on. The PTC is designed to be unobtrusive and you can still over draw the battery if you aren’t paying attention. PTC circuits can also fail if exposed to static electricity or from a faulty charger. When a PTC fails, it often fails in a position which allows you to continue using the battery without fault. I am currently unaware of any testing methods for the PTC outside of complex tests from specifically designed machinery. If you believe your PTC may have been impaired, it’s better to be safe than sorry and replace your battery. Some manufacturers will provide a CID, or Current Interrupt Device, instead of or alongside a PTC. The CID is very similar in function but will cut the connection to the battery
when signs of failure arise.
Ohm’s Law 101
Ohm’s law defines the relationship between Voltage, Resistance and Current or: I=E/R I = Voltage (V) E = Current (A) R = Resistance (ohms) If you are building your own coils, you should make yourself familiar with Ohm’s Law. This will allow you to calculate the draw on your battery before you fire it up for the first time and potentially push the battery past it’s limits. Basically, if I build a coil that has a resistance of 1.5 ohms, and I apply 4.0V across it: 4.0V / 1.5ohm = 2.6 Amps This means you will have a 2.6 amp current draw on your battery. If I was using an ICR18350, I would be pushing the limits of the battery while an IMR18350 would accept it with ease.
What exactly is an AW anyway?
Anybody who owns a Provari knows about AW from Provape’s nice little warning about voiding the warranty if a non AW battery is used. AW is the initials of a man Andrew Wan, who owns a China based company which purchases batteries from the big boys (Samsung, Panasonic, etc) and performs a quality test. Once the battery passes the quality test, they slap on a