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General => General Technical Chat => Topic started by: Boris_yo on October 18, 2022, 04:59:47 pm

Title: Wipe Off the Battery Before Use?
Post by: Boris_yo on October 18, 2022, 04:59:47 pm
Hi. What is the purpose for wiping off the lithium cell battery before using it?
I found it mentioned on a few websites.

(https://www.eevblog.com/forum/chat/wipe-off-the-battery-before-use/?action=dlattach;attach=1617568)
Title: Re: Wipe Off the Battery Before Use?
Post by: ataradov on October 18, 2022, 05:26:01 pm
I would assume they don't want the finger grease and sweat to cause oxidation and poor contact over time.
Title: Re: Wipe Off the Battery Before Use?
Post by: pcprogrammer on October 18, 2022, 06:56:46 pm
And to not create a restive bridge between the two poles, which shortens the battery life. Best to touch these batteries as little as possible.

I usually try to leave it in the plastic and slip it into place without touching it at all.
Title: Re: Wipe Off the Battery Before Use?
Post by: james_s on October 18, 2022, 08:42:50 pm
It's the latter. Finger oils contain salts and these combined with moisture forms a slightly conductive film. It's not much, but when spread over the multiple years these small cells can last it doesn't take much leakage current to significantly reduce the lifespan.
Title: Re: Wipe Off the Battery Before Use?
Post by: Boris_yo on October 19, 2022, 12:44:50 am
This is only relevant to CR2032 and similar sized lithium cell type batteries? What about small sized batteries like LR44 and AG3? And lithium/alkaline AAs/AAAs? 9v rectangular battery?
Title: Re: Wipe Off the Battery Before Use?
Post by: ataradov on October 19, 2022, 12:50:21 am
It is relevant for all types of batteries, but it has most impact on small batteries that don't have a lot of capacity to begin with. Discharging even AAA battery though dirt and grime traces would take a while and self discharge would likely to be higher anyway.
Title: Re: Wipe Off the Battery Before Use?
Post by: Halcyon on October 19, 2022, 03:25:05 am
I was always taught to give contacts and button cells a clean with alcohol when replacing them. So I've always done it that way. I mean, if for no other reason that it's nice and clean.