Looking for battery technical info

[ChrisA]

I'm looking for a discharge curve that shows voltage as a function of remaing charge. I know rechargables start off at 1.2V and of course drop to zero when they ar 100% dead. But what exactly happens along the way? It likely depends on the rate of discharge so I'm looking for a family of curves. Anyone know of a good source for technical info in various battery types?

 

[jonnythan]

Here's my graph from a burn test on my 12V NiMH pack. This is pretty typical for NiMH batteries.

NiMH's and Li-Ions have a flatter discharge than alkaline batteries. See http://www.zbattery.com/rechargeablebatteries.html

 

[jonnythan]

I'm looking for a discharge curve that shows voltage as a function of remaing charge. I know rechargables start off at 1.2V and of course drop to zero when they ar 100% dead. But what exactly happens along the way? It likely depends on the rate of discharge so I'm looking for a family of curves. Anyone know of a good source for technical info in various battery types?

BTW, NiMH's don't start at 1.2V, as you can see on the charts. My 10 cell pack generally starts off at almost 14 volts (1.4V per cell), then doesn't reach 1.2V per cell until it's over halfway to being dead.

 

[Charlie99]

I'm looking for a discharge curve that shows voltage as a function of remaing charge. .......... It likely depends on the rate of discharge so I'm looking for a family of curves.

THe manufacturers have lots of info on the internet. http://www.duracell.com/oem/Pdf/others/TECHBULL.pdf , for example shows discharge curves at C and 0.2C rates at 3 different temps.

http://sanyo.wslogic.com/pdf/pdfs/HR-3U-1700.pdf shows 0.2C, C and 2C discharge curves for the 1700mAh Sanyo's NiMH AA.