# Peltier behaves strangely

I've been trying to test my Peltier moodule (tec1-12706) with 2 1.3V batteries (2.6 in total in series) connected parallel to the module..

|+ -| ------|Peltier +|
|- +|-------|Module  -|


The batteries are full and show 2.6 volts. But when I measure the voltage drop on the Peltier it shows only 2 V and it draws only 200 mA max (according to TEC1 12706 datasheet it should draw 1 A.

Am I missing something?

• Are your batteries capable of supplying 2 A? (A datasheet for the battery would be helpful) – The Photon Apr 21 at 14:52
• Not knowing your level of experience I have to also ask, 1. How did you measure the TEC current? 2. What kind of heat sink did you use on the hot side? 3. How much heat is the thermal load on the cold side producing? A photo of your setup would be helpful. – The Photon Apr 21 at 14:54
• Did you have any heatsinks or thermal measurements? were both batteries exactly equal? – Sunnyskyguy EE75 Apr 21 at 19:51
• If your meter reads 2.6V for 2 unloaded batteries and reads 2.0V for the same batteries at a 200mA load, it would appear your batteries each have 1.5$\Omega$ internal resistance. – K H Apr 21 at 23:48
• What type of battery is 1.3V nominal? – Hearth Apr 21 at 23:50