9V lithium primaries for multimeters? - Page 1
Forum section: electronics / testgear

author: knotlogic
author_rank: Regular Contributor
timestamp: May 23, 2017, 03:39:21 am
content: I think I may have asked about this quite a while back, but I recently had a thought and went looking for new information.The question is, is it OK to use a 9 V lithium primary in a multimeter that normally uses alkalines? I think at least one of the Keysight DMMs says yes in its manual, but not in their others. The main benefit I see is that there's less of a worry about a leaking alkaline cell in a DMM that's only occasionally used.Energizer has datasheets for their batteries, and I went to look at what they say about their9 V alkaline, and their9 V lithium. According to their discharge plots, the alkaline starts at 9 V, and the lithium starts just a tiny bit above. Eyeballing it, I'd say no more than 9.2 V.Now on a meter like the U1252B that has a built in NiMH charging option, I believe I saw somewhere that an NiMH cell hot off the charger can be as high as 10 V. If that is indeed the case, and the DMM can handle that, would that mean it's safe to make use of a 9 V lithium primary instead?

author: edavid
author_rank: Super Contributor
timestamp: May 23, 2017, 05:11:22 am
content: Why don't you use an 8.4V Li-ion rechargeable?

author: knotlogic
author_rank: Regular Contributor
timestamp: May 23, 2017, 05:33:47 am
content: It's an option, but I haven't seen any for sale here, and shipping restrictions on Li-ion makes that infeasible.

author: PowerNet
author_rank: Regular Contributor
timestamp: May 23, 2017, 05:41:08 am
content: Would like to know this too.Is it ok to use on a Fluke 87V ?

author: Nusa
author_rank: Super Contributor
timestamp: May 23, 2017, 05:56:52 am
content: As a general rule, I'd say you can use the 9V Lithium in just about anything that can use a 9V Alkaline. It'll last longer and have a better discharge curve before falling below the critical voltage of the meter. It'll also cost more.Get a NiMH battery if you want to use a NiMH charging circuit....don't try to charge any other type of battery with it.

author: exor
author_rank: Regular Contributor
timestamp: May 23, 2017, 06:10:57 am
content: I have Fluke 87 (first version, +25 years old) and two Fluke 8025A’s and they all work well with 9 V lithiums.

author: med6753
author_rank: Super Contributor
timestamp: May 23, 2017, 10:21:43 am
content: Quote from: exor on May 23, 2017, 06:10:57 amSame here. Using lithiums in 1997 vintage Fluke 87 with no issues. To Op....use with confidence.

author: knotlogic
author_rank: Regular Contributor
timestamp: May 23, 2017, 01:50:09 pm
content: Thanks guys. Though mine is a Keysight rather than a Fluke. I'll let you know if anything explodes!Quote from: Nusa on May 23, 2017, 05:56:52 amYep, don't plan on charging anything in the meter. I'm looking at lithium primaries.

author: David Hess
author_rank: Super Contributor
timestamp: May 23, 2017, 03:09:23 pm
content: There is no problem using lithium 9V batteries to replace alkaline 9V batteries however the economics are questionable and leakage is less of a problem with alkaline 9V batteries because they are double enclosed.

author: james_s
author_rank: Super Contributor
timestamp: May 23, 2017, 05:02:02 pm
content: I can't see any reason why not. I use an 8.4V LSD NiMH in my Fluke 87 and it's been great. I have two of them and just swap them when one gets low and put the other on the charger.