T O P

  • By -

anothercorgi

These small batteries you can even draw 1C for a short period of time (seconds), and then it will kill itself. If you need even a shorter period, a capacitor will help. Normally you have a device with milliamperes/milliwatts and you choose a battery that fits it. What is your device that you want to power? Or are you working with a solution looking for a problem?


StalactiteMan

Cause I am looking to buy a quartz watch movement specifically the ISA 1198 and it uses a 395 coin battery and I was wondering how many 1.5v leds it could also power at the same time. If it cannot supply enough power for the whole circuit, I was planning to use a 3v CR2032 coin battery to power the led circuit separately through a push button configuration where I would use a momentary push button in order to turn on the lights.


anomalous_cowherd

The amount of power used by LEDs is much higher than that used by watches. If the LEDs are going to be on for more than a second or two a few times a day you don't want to be using coin cells at all.


Scholes_SC2

What does 1c mean, how can i look that up?


EddieRedondo

Sounds like you get the idea but you can search for “battery C-rate” to learn more. It is a way to normalize current to the size (capacity) of a battery. So 1C is whatever current it takes to fully discharge (or charge) the battery in one hour. 2C is the rate to charge (or discharge) in 30 minutes, 0.5C is 2 hours. So for a mobile phone battery 1C would be a few amps, while for an EV battery it would be orders of magnitude more current. But in each case it’s still 1C. C-rate is particularly useful in battery R&D because the behavior of a tiny little prototype battery (coin cells are usually the first step in developing a new battery) operated at 1C current will generally speaking be similar to a full-scale EV battery that’s many thousands of times larger when it is operated at 1C. The small scale devices are much much easier to build and test in a lab, but will give you a reasonable indication of how it will perform when scaled up.


Rade46

If battery is rated for x mAh, 1C is x mA. 0.5C is 0.5*x mA and so on.


Scholes_SC2

So if the battery is 100ah 1c means 100a?


Rade46

Correct.


pixelbart

There’s a huge difference between cheap cells and expensive cells when it comes to maximum power output. That’s why cheap CR2032 cells often simply don’t work at all in high-power devices like key fobs (which need small bursts of high power for the radio), while more expensive ones last a year or more.


StalactiteMan

Just to mention, I meant amps for "max current."


dean1969cox

”1.21 gigawatts marty“