e2000 MPU Battery Replacement

[Chaos]

Some of the advice I have read, says that you should add a 1N5817 diode and then use a Li Ion battery instead of the standard fitted Ni Cad battery that usually needs replacing.
What if I want to use a NiMH battery instead, like this one instead of the Li Ion? https://www.mantech.co.za/ProductInfo.aspx?Item=310M0082



Can I use a NiMH rather than go to a Li Ion and if I do, do I need to add the diode? I assume this is the correct diode? https://www.mantech.co.za/ProductInfo.aspx?Item=72M0616



Or should I just use this NiCad instead with no mods? https://www.mantech.co.za/ProductInfo.aspx?Item=15M0260



Or go with this Li Ion and use the diode as originally mentioned? https://www.mantech.co.za/ProductInfo.aspx?Item=15M0456



Which of the above options would be best?

• Li Ion with diode
• NiMH with or without diode or what other mod?
• Ni Cad shown above, more modern version of original?

All appear to be 3.6V, so it just depends on which do you guys recommend as best? All seem to have wires/mounting plates that should make it easy to solder in.

Thanks.

[qbert]

 

[Chaos]

Does no-one know, or am I asking a dumb question?
I suspect the latter 

[Chris-socal]

Their point being, you can use a lithium battery as backup but they are not rechargeable and will burst if you drop it into a circuit that is intended to charge a nicad battery. The diode only allows power to come out of the battery when the machine is turned off. It’s essentially a one way valve.

IMO, either way you will end up replacing a battery of some type in a few years. Im not sure why they recommend using Lithium, maybe because the expected shelf life is longer?

Chris

[Chaos]

Ah! I gotcha.
I assumed the setup was to allow for a rechargeable Li Ion. I see what you mean, they are using the diode to prevent charging, and only allow power out.
So it's a long term disposable battery?

So what happens if we add a rechargeable NiMH or Li Ion? I guess bad stuff.

What if I add that rechargeable Ni-Cad above? That should be similar specs to what was in there, and I should be able to add it without a diode? Does that sound do-able?

[Chris-socal]

If it had a NiCad you can use same capacity or higher of Nicad or NiMh
Lithium isn’t typically used in a circuit that has constant current applied.

[Badbaud]

The move away from NiCads and NiMH batteries is because they tend to leak out a chemical that eats traces and socket contacts.