Replacing ER3 3.6V battery with couple of button cell batteries

One of fixes I did to my Laptop 386sx was replacing of ER3 3.6V battery with couple of button cell batteries.

ER3 3.6V battery in Laptop 386sx

I did not have ER3 batteries and I did not want to buy and wait for one. So I took couple of CR2025 batteries I had near by, one small signal diode and some random connector and made a new battery that can be easily replaced later.

Small signal diode and two CR2025 taped together with some leads, ready to be installed.
New connector soldered instead of ER3 with improvised battery pack of two 2025 connected.

You need to use diode to prevent charging, just in case.

1 Comment

  1. Hello,

    Do you have more pictures of the motherboard of the twinhead superlap?

    I’m restoring one myself, but because of waterdamage, I cannot read the numbers anymore on top of the quartz crystal components. (the 6 square ones).


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