Re: [EE] Storing lithium thionyl chloride batteries on a shelf for 2 years?

On Fri, 4 Jul 2025 at 03:42, Jason White <[email protected]>
wrote:

> Lithium thionyl chloride batteries go bad when no load is applied to them.
> They must have a load applied periodically or they will go open circuit
> within a few months. I've got a situation where I need to store a large
> number of ER18505
> lithium thionyl chloride batteries on a shelf for one to two years.
> I was wondering if any commercial products exist to accommodate this need?
> (it would be something that connects to or holds the batteries and
> periodically applies a small load to keep them alive
>
> I read a little on this recently due to a query on Stack Exchange.
I have zero practical experience.

You may well be right, but I HOPE that you are wrong.
Based on what I read it appears that you can recover their normal state
after a period of inactivity by applying a suitable "depassivation" load
for a period.

*Update*: I've just read a few references and I'm reasonably sure that you
do not have to worry about passivation during storage - and in fact this is
what gives them their long shelf life.

The only downside is that they need a current x time depassivation burst to
bring them up to normal condition.
A large parallel capacitor may assist in wakeup performance.

The mechanism is oxidation which is removed by the depassivation charge.
To maintain the cells in a continuing "good" state the current x time
bursts were very unattractive compared to operating them at a "safe" level
continually.
From memory the minimum current for the cell in question was 30 uA and the
claimed depassivation "bursts either weekly or monthly produced a net
uA-second drain about the same as 30 uA continuous.

At a quick skim the following papers, mainly from reputable manufacturers,
seem to confirm what I said and also add some useful advice.
As ever, I may be wrong :-)

This seems to conform what I said AND was probably the page that gave me
the information with required "stay awake" bursts
https://www.jauch.com/blog/en/passivation-lithium-thionyl-chloride-batteries/

SAFT - gotta be good for you :-)
The seven passivation pitfalls (and how to avoid them)

https://saft.com/en/energizing-iot/seven-passivation-pitfalls-and-how-avoid-them

Tadiran (them too)
Understanding the passivation effect
https://tadiranbat.com/wp-content/uploads/2022/03/Tadiran-White-paper-Understanding-Passivation-bottles.pdf

Lithium Battery Passivation and De-Passivation
https://www.swe.com/media/files/files/114e6391/lithium-battery-passivation-de-passivation-whitepaper.pdf

AceOn Explains: Passivation & Lithium Batteries
https://www.aceongroup.com/news/aceon-explains-passivation-lithium-batteries/

Google -
<https://www.google.com/search?q=thionyl+chloride+cell+passivation&num=10&sca_esv=08d7cfad2e6e3e53&rlz=1C1ONGR_enNZ1122NZ1123&sxsrf=AE3TifNAQt7kRiLgeKBQK3Y6v0AXWHM66Q%3A1751559761217&ei=Ua5maIKGDb-a0-kPiMPvmQI&ved=0ahUKEwjC8vrKjKGOAxU_zTQHHYjhOyMQ4dUDCBA&uact=5&oq=thionyl+chloride+cell+passivation&gs_lp=Egxnd3Mtd2l6LXNlcnAiIXRoaW9ueWwgY2hsb3JpZGUgY2VsbCBwYXNzaXZhdGlvbjIFECEYoAEyBRAhGKABSMM5UMUaWJ4ycAF4AJABAJgB6QGgAb8RqgEFMC42LjW4AQPIAQD4AQGYAgygAv0RwgIOEAAYgAQYsAMYhgMYigXCAggQABiwAxjvBcICCxAAGIAEGLADGKIEwgIEECEYFcICBRAhGJ8FwgIHECEYoAEYCpgDAIgGAZAGBJIHBTEuMy44oAfLI7IHBTAuMy44uAfzEcIHBTAuNy41yAcq&sclient=gws-wiz-serp>thionyl
chloride cell passivation
<https://www.google.com/search?q=thionyl+chloride+cell+passivation&num=10&sca_esv=08d7cfad2e6e3e53&rlz=1C1ONGR_enNZ1122NZ1123&sxsrf=AE3TifNAQt7kRiLgeKBQK3Y6v0AXWHM66Q%3A1751559761217&ei=Ua5maIKGDb-a0-kPiMPvmQI&ved=0ahUKEwjC8vrKjKGOAxU_zTQHHYjhOyMQ4dUDCBA&uact=5&oq=thionyl+chloride+cell+passivation&gs_lp=Egxnd3Mtd2l6LXNlcnAiIXRoaW9ueWwgY2hsb3JpZGUgY2VsbCBwYXNzaXZhdGlvbjIFECEYoAEyBRAhGKABSMM5UMUaWJ4ycAF4AJABAJgB6QGgAb8RqgEFMC42LjW4AQPIAQD4AQGYAgygAv0RwgIOEAAYgAQYsAMYhgMYigXCAggQABiwAxjvBcICCxAAGIAEGLADGKIEwgIEECEYFcICBRAhGJ8FwgIHECEYoAEYCpgDAIgGAZAGBJIHBTEuMy44oAfLI7IHBTAuMy44uAfzEcIHBTAuNy41yAcq&sclient=gws-wiz-serp>



          Russell