Transformer isolation.

http://www.edn.com/design/analog/4327228/Novel-measurement-circuit-eases-ba=
ttery-stack-cell-design

What is going on here is you generate a pulse stream through a=20
relatively high impedance source and apply that to the primary winding=20
of a transformer, the secondary of the transformer is connected through=20
a diode to the battery be measured, the primary of the transformer will=20
be clamped to the secondary voltage as it tries to "charge" the battery.=20
You then measure the primary. The article explains it better and details=20
the other things that need to be considered.

I don't know what the OP is measuring or it's impedance - this may not=20
be suitable.

Trevor
--=20
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