Identifying (old?) Sanyo 18650 batteries UR18650A; safe to use?

spoolin01

Newly Enlightened
Joined
Dec 31, 2005
Messages
15
I found a too-good-to-be-true price on some new 2200MAh 18650 batteries on eBay, said to be Sanyo UR18650A


  • the pink/red sleeve is impressed with "Japan M36A"
  • there are two other strings printed in large digits made of dots: MHIA2B, with a 6 digit number below - a different one on each battery; also a small bold B. I think these are printed on the sleeve, but can't be sure that they aren't showing through.
  • there are numbers printed about the periphery of the bottom of the cell, a different number and pattern of the number on each one.
  • there is a purple ring around the positive terminal
  • no other ID marking on the sleeve, specifically no "Sanyo" or "UR18650A"

Can anyone shed any light on these? Googling MHIA2B doesn't return any answers. My first thought was that these were just being fobbed off as Sanyo, but I can't really tell from what little I know. If the embossed string can be taken to be a Sanyo date code, these appear to be from 2008.

If these are indeed that old - NOS - is it safe to use them in a high drain application? Current Sanyo UR18650A cells seem to be rated to 4.3A.
 

ChrisGarrett

Flashlight Enthusiast
Joined
Feb 2, 2012
Messages
5,726
Location
Miami, Florida
M-3-6 denotes that they're made in September, 2008, so they're almost 9 years old.

https://batterybro.com/pages/18650-date-code-lookup-tool

2200mAh seems about right for the time.

Can't vouch for authenticity.

Data sheet:

https://na.industrial.panasonic.com...files/panasonic-li-ion_ur18650a_datasheet.pdf

I wouldn't stress them. No more than 2A, maybe 3A if I was Chuck Connors hosting Thrill Seekers again. When they were new, the data sheet shows a 3C discharge, or 6.6A, but that was for a fresh cell.

Standard charge current is 1.5A to 4.20v, again when they were new.

Chris
 

spoolin01

Newly Enlightened
Joined
Dec 31, 2005
Messages
15
Here's a spec sheet from 2008, when these were still made by Sanyo. The current Panasonic version you linked to seems to have better high drain characteristics. I'm going to try a 2C discharge cycle and see how well the units I received match even the old profile. Still have to decide whether to call BS on these and make the seller take them back. Just the fact that they are 9 years old and that wasn't disclosed chafes me.

http://www.meircell.co.il/files/Sanyo UR18650A.pdf
 

apashi

Newly Enlightened
Joined
Jan 5, 2018
Messages
2
Hello,
Can you help my find the model and specs for this batteries from old laptops?
One is Red Sanyo with green ring and the other is Sony US17670GR.
Thanks!
 
Top