Question 2xRCR123a = 2000mA

[lukevsdarth]

Hello, i am trying to figure out on the Led pro calculator if each battery is 1000mA and theres two of them together will they equal 2k mA (2A) 3.7+3.7=7.4 . Thanks in advance forum.


Fred:twothumbs

 

[half-watt]

Hello, i am trying to figure out on the Led pro calculator if each battery is 1000mA and theres two of them together will they equal 2k mA (2A) 3.7+3.7=7.4 . Thanks in advance forum.


Fred:twothumbs

only in a parallel arrangement, not in the far more common (for flashlight purposes) series arrangement.


btw, i have some RCR's from two different sources that are labelled as 1000mAh cells. at least that's the Manufacturer's story and they're sticking to it!!

cells are normally rated for their capacity from a fully charged voltage, whatever that would be for a particular type of cell, down to some chosen cut-off voltage. sorry, i don't know what that would be for RCR's - some state 3.0VDC, some as low as 2.75VDC). whether all of that stored energy will be "tapped"/utilized depends upon a number of factors, not the least of which is the design of the application that you are using it in, and, in the case of some lights, how low of an output you are willing to live with before changing cells. another factor that comes into play is the rate of discharge, and also any recovery periods that the battery experiences. this is NOT to say that it is necessarily a good thing to try to drain those little suckers "dry", so to speak - sometimes bad things can happen with Li-ion and Primary Li cells also.

 

[DM51]

If you are talking about capacity, the answer is no. To start with, there is no R123 in existence with a capacity of 1,000mAh. Despite what may be printed on the cell wrapper, ~750mAh is the max capacity of these cells, and under load it will be barely more than 500mAh. So you won't even get 2,000mAh in parallel.

 

[yellow]

3.7 + 3.7 = 7.4 V --> 1000 --> in series
1000 + 1000 = 2000 --> 3.7 V --> in parallel

 

[x2x3x2]

Basically what yellow stated.

In series you get double the voltage (7.4V) with the capacity of a single cell (1A).
In parallel you get double the capacity (2A) with the voltage of a single cell (3.7V).

You won't double both.

 

[LukeA]

You won't double both.

Unless you use four cells.

 

[sysadmn]

3.7 + 3.7 = 7.4 V --> 1000 --> in series
1000 + 1000 = 2000 --> 3.7 V --> in parallel

Also, you need to find out if you're looking for capacity (mAH) or current (mA). As an absurd example, a 1000mAH battery can't deliver 1000 A for one-thousandth of an hour. If you're interested, search for "C discharge rate"

The charge and discharge current of a battery is measured in C-rate. Most portable batteries are rated at 1C. This means that a 1000mAh battery would provide 1000mA for one hour if discharged at 1C rate. The same battery discharged at 0.5C would provide 500mA for two hours. At 2C, the 1000mAh battery would deliver 2000mA for 30 minutes. 1C is often referred to as a one-hour discharge; a 0.5C would be a two-hour, and a 0.1C a 10-hour discharge.

More info about Li-Ion is here. I was amazed to read there's a Li chemistry that supports continuous 35C discharge - apparently they're available for the Segway. Wonder what those batteries cost?