DMM battery question  - Page 1
Forum section: electronics / general

author: Russ
author_rank: Regular Contributor
timestamp: December 02, 2017, 04:11:21 pm
content: HelloWhy are so many people opposed to meters that use the little 9v battery?ThanksRuss

author: saturation
author_rank: Super Contributor
timestamp: December 02, 2017, 04:54:21 pm
content: AA and AAA are more widespread, so others feel 9V are no longer necessary. There are many power management circuits that can easily take the lower 1.5V of an AA, or multiples of them, and boost them to whatever is necessary. Alkaline AAA typically 1Ah and AA 2Ah capacity, which will reduce the need to change batteries and overall, reduce waste production.That said, AA/AAA alkaline manufacture has become so poor, they are likely to leak and damage the internals particularly with the reduced need to change them frequently.9V alkaline very rarely leak, because they are double housed but they are typically only0.20.50Ah [my error, 0.250Ah is NiMH 9v as another posted] , and also cost more, and may require changing more often.AA, AAA, and 9v exist in Lithium primary and secondary chemistry, as well as secondary NiMH, these cells rarely if not ever leak and all have much great Ah for longer life and should be your go-to chemistry to replace alkaline in whichever DMM you choose.

author: rdl
author_rank: Super Contributor
timestamp: December 02, 2017, 05:07:43 pm
content: 9 volt batteries are ridiculously expensive for the tiny amount of power they contain. I always tried to avoid buying anything that used them. Then about six months ago I bought some 9 volt NiMH and Lithium ion batteries and a charger. Now I don't mind them so much.

author: HKJ
author_rank: Super Contributor
timestamp: December 02, 2017, 05:55:02 pm
content: 9V primary batteries are about 600mAh:http://lygte-info.dk/review/batteries9V/Common9Vcomparator.phpBut AAA batteries are about 1000mA and two or 3 of them are much cheaper.Most multimeters need 2 to 3V and will use a linear regulator to drop a 9V batter down to that range.In multimeters I use for logging I prefer AA batteries (2800mAh), but for more occasionally use I do not really care. My current go to meter uses a 9V battery (Keysight U1252B).

author: David Hess
author_rank: Super Contributor
timestamp: December 02, 2017, 06:08:59 pm
content: Energy density for AAs and AAAs is better than for a 9 volt battery even after switching regulator losses are taken into account (1) and they have a better energy/cost ratio. Very good inexpensive low discharge AA and AAA NiMH cells are available while rechargeable 9 volt batteries are expensive and of questionable quality.A 9 volt battery with a linear regulator has an advantage with noise but with careful design, this is not a problem for a switching regulator and 1.5 volt cells.But all of my handheld multimeters use 9 volt batteries and I have no complaints about that aspect of their operation.(1) Linear Technology used to have a trade magazine advertisement about "how to suck a 9 volt battery dry" which compared 9 volt and 2 x AA cell performance with different voltage regulator configurations.

author: HKJ
author_rank: Super Contributor
timestamp: December 02, 2017, 06:23:13 pm
content: Some comparable values:9V Alkaline: 4.8Wh, but because DMM's often use linear regulators they waste maybe half the energy.AAA Alkaline: 1.1WhAA Alkaline: 3WhValue will vary with load and battery quality, the above values are with a low load (Like a multimeter).

author: Electro Detective
author_rank: Super Contributor
timestamp: December 02, 2017, 09:05:50 pm
content: Regardless of the power math, AA and AAA batteries are more likely to leak, regardless of price or brand BS.I have lost 2 good meters because of that, and a few leakers I managed to save just in time before the crud got into the electronics and switch selector tracks.I have NEVER had a leak issue with 9 volt batteries (cheap or Duracell) in any meter, be it a cheapie or Fluke 87x etcSuggest to check all equipment with AA and AAA batteries every 3 to 6 months, especially in hot/humid climate

author: HKJ
author_rank: Super Contributor
timestamp: December 02, 2017, 09:19:58 pm
content: Duracell is very bad a leaking in my experience, other brands, even cheap ones, are not that bad.

author: rdl
author_rank: Super Contributor
timestamp: December 02, 2017, 10:28:04 pm
content: If you're concerned about leaks then don't use alkaline batteries. I've heard rumors that NiMH can leak, but I've never seen it happen. I've seen dozens of leaking alkalines though. I only have four alkaline batteries left. They're in remote controls. They will be replaced with NiMH when the time comes.

author: Russ
author_rank: Regular Contributor
timestamp: December 03, 2017, 05:00:49 pm
content: Thanks for the replies. I have been using rechargeable Eneloop AA & AAA batteries for quite some time now. I? have never had one leak. Duracell alkalines have been a nightmare. 😬

author: David Hess
author_rank: Super Contributor
timestamp: December 03, 2017, 07:23:23 pm
content: NiCd and NiMH cells can leak but the result is a lot less destructive because the volume of electrolyte is low. Typically the only sign is that the positive terminal looks "fuzzy" from potassium hydroxide crystals.

author: Russ
author_rank: Regular Contributor
timestamp: December 03, 2017, 07:42:29 pm
content: Quote from: HKJ on December 02, 2017, 09:19:58 pmI agree. They are known to leak.

author: nes999
author_rank: Contributor
timestamp: December 07, 2017, 04:28:48 pm
content: I get AAs, AAAs for free from work. So is rather not buy over priced 9v batteries. I agree with others Duracells seem to leak often. I personally only use Rayovac.

author: Electro Detective
author_rank: Super Contributor
timestamp: December 07, 2017, 10:02:54 pm
content: Nowadays I use any battery brand that's cheap, appears well made with decent packaging and quality/power claims, and used previously with no problems.But I stick with overpriced Duracell 9v in smoke detectors because they appear to be the 'standard'...think 'Insurance Policy' going south if the smoke detector/s failed, the house or business premises are toast,and the 'bad hair day' claims investigator spots the 2006 dated, leaking 50 cent'TooHungLo Pwoer Baterry'installed.When swapped out yearly the used 9v Duracells go into multimeters, so I get the most bang for buck on them.

author: 6PTsocket
author_rank: Regular Contributor
timestamp: January 16, 2018, 06:41:45 am
content: Quote from: Electro Detective on December 02, 2017, 09:05:50 pmJust cleaned up after a leaker yesterday. Plain distilled white vinegar and a Q tip. It often looks worse than it is. Some alkalines seem to leak worse than others Practically every damn one of the Kirklands (Costco house brand) leaked on me in the last batch . I think they are made by Duracell. Better luck with Pannasonic and Harbor Freight's Chinese house brand AA and AAA.Sent from my SM-G900V using Tapatalk

author: 001
author_rank: Super Contributor
timestamp: January 16, 2018, 09:49:41 am
content: Quote from: David Hess on December 02, 2017, 06:08:59 pmit is interesting! how to find this article?

author: HKJ
author_rank: Super Contributor
timestamp: January 16, 2018, 09:58:56 am
content: With data from my website is is fairly easy to compare AAA/AA/9V batteries:9V:http://lygte-info.dk/review/batteries9V/Common9Vcomparator.phpAA/AAA:http://lygte-info.dk/review/batteries2012/CommonAAcomparator.phpThere is also 3 comparators for different sizes LiIon batteries.You have to select the individual reviews to get Wh curves that can be compared independent of voltage and I do not include any looses to regulators.

author: bd139
author_rank: Super Contributor
timestamp: January 16, 2018, 10:40:59 am
content: Just a point that no one has made. A rare event but worth mentioning. Sometimes 9v batteries explode. I'm not talking about the phoney crap you see on youtube or shorting them on anything, but they do explode spontaneously sometimes. I have seen this first hand twice in 30 years and my sister has seen it as well; she worked for a supermarket distribution company which handled crates of the things. All were major brand in date batteries stored in original packaging. Usually one of the cells explodes and blows the end off. Makes one hell of a bang.Never heard of that for AA's; they just leak! Apart from GP Ultra; have used thousands of them and they don't seem to leak at all.One reason I bought a Keysight U1241C was it doesn't take 9v batteries.

author: HKJ
author_rank: Super Contributor
timestamp: January 16, 2018, 10:52:00 am
content: Quote from: bd139 on January 16, 2018, 10:40:59 amMost 9V batteries are fairly leaky in construction and cannot explode. You can see how they are build here:http://lygte-info.dk/info/BatteryDisassembly9VAlkaline%20UK.html

author: bd139
author_rank: Super Contributor
timestamp: January 16, 2018, 11:13:01 am
content: It's always the middle cells in the flat packed ones that go bang. They sure can explode!Incidentally both the ones I had blow up were Duracells.

author: David Hess
author_rank: Super Contributor
timestamp: January 16, 2018, 12:15:25 pm
content: Quote from: 001 on January 16, 2018, 09:49:41 amIf you want to look through old issues of Electronic Design or Electronic Design News, then you can find it. It was just an advertisement although a humorous one.Linear Technology design note 63was based on it.

author: rrinker
author_rank: Super Contributor
timestamp: January 16, 2018, 03:53:40 pm
content: The controllers for my model railroad us 9V batteries, and they don't last very long - one thing I wanted to do was alter them to use 2x AA instead. I think even just replacing the stock regulator with an LDO type would work, as they get erratic at about 8.6V measured across the battery under load.

author: Russ
author_rank: Regular Contributor
timestamp: January 16, 2018, 05:31:05 pm
content: I prefer to use rechargeable Eneloops. But for almalines, the AC Delco batteries have always worked very well and never leak on me. Plus, they are very cheap on Amazon.

author: 001
author_rank: Super Contributor
timestamp: January 16, 2018, 07:03:33 pm
content: Quote from: Russ on January 16, 2018, 05:31:05 pmAnd what type of rechergeable9Vbatts You can reccomend for DMMs like 87V?NiMH vs Li-Ion?

author: HKJ
author_rank: Super Contributor
timestamp: January 16, 2018, 07:06:16 pm
content: Quote from: 001 on January 16, 2018, 07:03:33 pmFor 9V batteries LiIon is the way to go: 3 times capacity of NiMH and very low self discharge.But you have to use the meter a lot, before there is any reason to use a rechargeable battery in it.

author: Rick Law
author_rank: Super Contributor
timestamp: January 17, 2018, 06:46:46 pm
content: Quote from: 001 on January 16, 2018, 07:03:33 pmI recommendTenergy Centura 9V (NiMH-LSD Rechargeable). I did a mini review long time ago (2013). The pair I used back then is still going strong today. I have since acquired more Tenergy Centura9V's and I am very satisfy with Tenergy performance. They are displacing my 9V primaries as they expire/died.It is only 200mAH, but there is a number of reasons to go with that, 7-cell instead of 6, LSD, etc. Most of all, I can use a freshly recharged cell each time I do long duration logging because I know what it will run for X hours continuous -- whereas a larger mAH primary that has been in used for a while might have far less left and I would not know.You will find more info about that battery in my mini review here:https://www.eevblog.com/forum/reviews/tenergy-centura-9v-and-tn141-mini-review/Even with AA/AAA, Tenergy is now my day-to-day use stuff and are beginning to replace my Eneloop (AA) I keep for emergencies.By the way, two more things:- Take particular note on the length of the battery compartment (see my review). They are 7 cells, while overall length (with buttons) is the same, the body is a bit longer.- Do make sure you order from reputable suppliers. I would not be surprised if you find fake Tenergy cells out there.

author: Russ
author_rank: Regular Contributor
timestamp: January 17, 2018, 06:55:05 pm
content: Quote from: Rick Law on January 17, 2018, 06:46:46 pmI recently purchase a set of Tenergy AAA cells. I was not aware that they were not LSD type batteries. But they seem fine. I haven’t had them long.Russ

author: Rick Law
author_rank: Super Contributor
timestamp: January 17, 2018, 08:31:45 pm
content: Quote from: Russ on January 17, 2018, 06:55:05 pmNot all Tenergy cells are LSD cells. You have to check the model. The Centura line is LSD. They have Centura AA/AAA (LSD) as well.I use the Tenergy Centura line as lower cost Eneloops. Not as good but more than good enough and more cost effective.

author: 6PTsocket
author_rank: Regular Contributor
timestamp: March 04, 2018, 08:03:51 am
content: Quote from: HKJ on December 02, 2017, 09:19:58 pmI had some Kirklands (Costco rebranded Duracells) and virtually every one of them leaked either in service or before use. On the other hand, the Chinese alkaines from Harbor Freight have yet to leak and seem to last fine. Leakage seems to be an inherent problem with alkalines.Sent from my SM-G900V using Tapatalk

author: 6PTsocket
author_rank: Regular Contributor
timestamp: August 26, 2018, 02:16:27 am
content: Quote from: saturation on December 02, 2017, 04:54:21 pmNiCds and NiMH batteries do not hold a charge that well. Lithium is much better. If you use the meter daily and don't mind frequently charging batteries, I guess they are OK. An alkaline has a 10 year shelf life, if it doesn't leak. Some brands are,worse than others.Sent from my SM-G900V using Tapatalk

author: HKJ
author_rank: Super Contributor
timestamp: August 26, 2018, 06:09:28 am
content: Quote from: 6PTsocket on August 26, 2018, 02:16:27 amModern NiMH can hold a charger for 10 years.

author: 6PTsocket
author_rank: Regular Contributor
timestamp: August 28, 2018, 01:23:43 pm
content: Quote from: HKJ on August 26, 2018, 06:09:28 amI think you are thinking of alkaline batteries. A quick search came up with the figure that NiMh cells can loose up to 40% of their charge in the first month, depending on temperature and other factors. I found this figure in several sites. You are so far from the generally available info that I would appreciate a link to where you got your info. NiMh self discharges even faster than NiCd. That is one if the reasons that they never caught on with power tool manufacturers. The only company I remember using them was Makita.Sent from my SM-G900V using Tapatalk

author: bd139
author_rank: Super Contributor
timestamp: August 28, 2018, 01:32:15 pm
content: https://en.wikipedia.org/wiki/Self-discharge#Typical_self-discharge_by_battery_typeLook at low-self-discharge NiMh.

author: HKJ
author_rank: Super Contributor
timestamp: August 28, 2018, 01:33:43 pm
content: Quote from: 6PTsocket on August 28, 2018, 01:23:43 pmI did not, old style NiMH could not hold their charge, but new style NiMH can. The are often called "Precharged".The best known brand is Eneloop (They are some of the best NiMH around).You can check Panasonics catalog:https://main.panasonic-eneloop.eu/sites/default/files/Catalogue_eneloop_ENG_2017_DEF_LR.pdfIt says 70% remaining energy after 10 years.

author: retiredcaps
author_rank: Super Contributor
timestamp: August 28, 2018, 07:37:40 pm
content: Quote from: 6PTsocket on August 28, 2018, 01:23:43 pmHKJ knows what he is talking abouthttps://lygte-info.dk/

author: Rick Law
author_rank: Super Contributor
timestamp: August 30, 2018, 02:31:14 am
content: Quote from: retiredcaps on August 28, 2018, 07:37:40 pm+1 to that!HKJ is my trusted source of info. Whenever I look for battery/charger, he (his website) is my number 1 source.