Saltwater batteries in series

[Zambaku]

Hello, I an having a bit of trouble with my saltwater batteries, I'm trying to hook them up to get more power but it is not working quite as I planned and could use some hints.

 

I get 0.20v from one saltwater cell, if I couple 2 together I get 0.40v, but if I add more, currently got 4 cells connected, I get 0.13v. They are hooked positive to negative and I use a multimeter to check the voltage, its called "Lini-T UT20B, the setting is the 1.5v battery testing.

I use Coper Wire for the positive, and aluminium foil for negative.

Hints would be greatly appreciated.

Edited August 21, 2018 by Zambaku
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