dry cell battery life question

[Munib]

A 1.5V dry cell have capacity of 2000mAh
Now if 4 of these cells are connected in series then will the overall capacity of these 4 cells will be 4*2000mAh or will remain only 2000mAh

Actually i want to drive a mcu at 5V with 1.5V dry cells.i have connected 4 cells in series and used an LDO regulator to get 5V.Now i want to know what will be Life of this battery system

 

[Sputnik]

Cells connected in series will always increase in voltage (1.5v × 4 = 6v) and capacity remain the same (2 000mAh).

Cells connected in parallel will always have the same voltage (1.5v) and increase in capacity (2 000mAh × 4 = 8 000mAh).

Hope this answers your question,
Sputnik :idea:

 

[purifier]

Can someone tell me what role this capacity plays... I've seen batteries ranging from 500mAH to 2500mAH... Is it that the battery can deliver 500mA of current per hour? Please help...

 

[Munib]

yes a 500mAh battery can provide 500mA current for one hour
For example if ur load draws 10mA current then your battery can provide this current for 500mAh/10mA=50 hours

 

[puviarasu]

Its like the liter of Pepsi or 2 liter of Pepsi that much is available for u. you can drink at the rate of 100ml per minute or 200ml per minute or 1liter per minute. You can use it until you can is empty.

 

[Cortex]

To have 8AH * 6V u need 16 Cells
but it to much because the Pic can work at 4.5v Range
so u will have only 12 that still Big if your project is a walking robot or a portable thing
so i recommand you to use GSM phone battery
it provide 3.6 - 5V and are very small

 

[sunsina]

If you Want to use Batteries in parallel for becareful to Use the Same Batteries
Both in Voltage and Model.

If you don't use same Batteries for Example if i use New (Sony 1.5 and Maxwell 1.5)
in parallel there is 3 problem.

1-Sony Bat may have 1.65 Volt on its end and Maxwell 1.55 (in the First Use Most
Batteries voltage are higher than their nominal Voltage)
So when you Don't use your device One of the Batteries Charge the Other One
and because You didn't use chargable Batteries the charged battery may Leak.

2-Because they Don't Have same Energy (mAh) for example Maxwell 1500mAh
and Sony 1000mAh So , Sony will Get Empty Soon!

3-Every Batteries Have internal Resistance which you can't find this By finding
Short Circuit Current and Battery Voltage.It Need special instrument

Batteries Capacitance are dependent to Age,Weather Conditions, and Humidity.

 

[ppenday]

current in series will be always same irrespective of number of 1.5v batteries u connect in series

 

[trigger74]

also noticed that the cell voltage will gradually dropped to 1.2V after sometime.... and it finally will gone after some hours of usage.
(the voltage curve depends on the manufacturer specification, I found they vary from brand to brand.....