Using Lithium Primary batteries in a DMM; is it help? - Page 1
Forum section: electronics / testgear

author: Nick1296
author_rank: Contributor
timestamp: March 30, 2017, 03:51:11 am
content: Since I picked up a new multimeter to replace my Craftsman 82141 (fuses are only sold in a kit with no specifics on what the size is) with a RadioShack 2200087 46 range meter, since it was on sale since the store here is closing. It uses AA batteries rather then a 9V battery, which is nice for convenience. Since I had Lithium batteries that were close, that's what I used in the meter. They were also the closest AA I had to hand at the time (TL;DR: I gave some of mine to someone, and they bought me a 4 pack to pay me back). Since I didn't pay for them, it doesn't hurt to try. When I have to buy more, my tone is going to be different based on the results of my Lithium runtime testing (how low do the batteries have to go for the readings to become unstable or lose accuracy?) The low battery indicator comes up at 2.5V (more on this later in the post).I've looked into the voltages for each type of battery. Alkaline is 1.5V. The total voltage is 3V (1.5x2). NiMh batteries are ~2.4V (1.2x2).Once you get to the Lithium cells, it's 1.8V/cell, which adds up to 3.6V (1.8x2). This is only a .6V increase, so not very substantial. I do not think I will get much extra runtime out of Lithium, based on those numbers. Maybe I will see an improvement, but I'm not holding my breath.The other thing I am confused about this meter on is why the low battery voltage of 2.5V (listed in the manual) and provided as an attachment. To me, 2.5V seems premature and seems VERY conservative. Maybe this is because of the data logging ASIC, though. If anyone can explain the idea behind such a early battery warning, I'm interested in why they set it so high. I may very well be missing something.Do Lithium batteries make a appreciable enough difference in runtime to justify the extra cost (it's ~$11-16 for 4 batteries)? The only pitfall I can see is the meter having the low battery indicator come up significantly early (or not showing up at all), relative to how long it will actually take with Alkaline or NiMh cells. All that really means is I really need to rely on accuracy to judge the health of the batteries, which I already do anyway. I will also need to carry around extra batteries (again, I already do this). If the cost doesn't make sense, I'm just going to buy Alkaline or NiMh batteries.

author: retiredcaps
author_rank: Super Contributor
timestamp: March 30, 2017, 04:27:16 am
content: For my DMMs that use AA or AAA, I use Eneloops or some equivalent LSD ni-mh. I can get 4 Ikea Ladda 2450 mAH AA LSD cells for $9 CDN. Or 4 Ladda 1000 mAh for $5 CDN.

author: Nick1296
author_rank: Contributor
timestamp: March 30, 2017, 04:46:25 am
content: Quote from: retiredcaps on March 30, 2017, 04:27:16 amYeah. I am having a hard time justifying Lithiums for the meter because of the cost. It's not hard in my backup digital camera but it's not something I am willing to stick to unless the runtime is appreciably improved to justify the cost.

author: retiredcaps
author_rank: Super Contributor
timestamp: March 30, 2017, 05:00:36 am
content: I have 3 older Canon digital cameras and they all take 4 AA. They all use Eneloops and can easily get 200 to 400 shots. More than enough for 1 day of shooting.I can't justify Lithium due to cost when I have multiple spare Eneloops.

author: retiredcaps
author_rank: Super Contributor
timestamp: March 30, 2017, 05:03:41 am
content: With rechargeable batteries, I also don't feel the need to reach of the off switch all the time. If I had lithium batteries, I would also be turning my device off/on multiple times to conserve its life.For my AA/AAA meters that have a backlight, I just leave the backlight on all the time as sometimes it helps when reading from a far or just makes the display easier to read. I don't care about run time as I just recharge the cells.

author: Nick1296
author_rank: Contributor
timestamp: March 30, 2017, 05:47:38 am
content: Quote from: retiredcaps on March 30, 2017, 05:00:36 amI have 4 I bought to keep around (Energizer Pro 2000mAh). They're nice to have but they're not the best. I should probably buy some better ones, like the Eneloops. However the storage drain sucks to the point I top them off every once in a while.

author: aargee
author_rank: Frequent Contributor
timestamp: March 30, 2017, 06:08:07 am
content: The big reason I'm going with lithium disposable batteries over alkalines - is that they, in my experience, don't leak corrosive crap throughout my devices (please let me know if anyone has experienced differently).They do seem to have a longer life, but this is anecdotal from this end.

author: Fgrir
author_rank: Regular Contributor
timestamp: March 30, 2017, 03:13:57 pm
content: Compare for yourself:http://data.energizer.com/pdfs/l91.pdfhttp://data.energizer.com/pdfs/e91.pdfFor low-load use I don't think the lithium justifies the cost delta unless you want it for one of the secondary properties like light weight, low-temperature performance, longer shelf-life, etc.

author: retiredcaps
author_rank: Super Contributor
timestamp: March 30, 2017, 04:52:08 pm
content: Quote from: Nick1296 on March 30, 2017, 05:47:38 amI can't find datasheet or brochure for the Pro series? Are these cells LSD (low self discharge)? The Eneloops are LSD. If it is an important day where I need my camera to work, I fully charge two sets.I do have some Energizer AA 2300mAH, non LSD, NI-MH and they lose all charge within 30 days or so.

author: james_s
author_rank: Super Contributor
timestamp: March 30, 2017, 05:10:36 pm
content: I use LSD NiMH cells in all stuff like this, mostly Eneloop, a few Fujitsu and some Amazon branded ones. I've never had any of them leak. I tried some of those lithium primary cells in a few things and was not impressed. They didn't seem to last any longer than ordinary alkaline batteries and they cost nearly as much as the cheaper NiMH cells.

author: IanB
author_rank: Super Contributor
timestamp: March 30, 2017, 05:16:31 pm
content: Quote from: james_s on March 30, 2017, 05:10:36 pmI'd have to check the data sheet, but I think the ultimate capacity of lithium primary cells in low drain applications is much the same as alkaline cells. It is only in high drain applications like cameras where lithium cells really have a strong advantage.

author: Nick1296
author_rank: Contributor
timestamp: March 30, 2017, 05:27:12 pm
content: Quote from: retiredcaps on March 30, 2017, 04:52:08 pmThe batteries are 2000mAh NiMh-HR6. Maybe that'll help, but if I find it myself I'll post it for you. They ship with the Energizer Pro charger, so I would not be surprised if the datasheet is hard to find. I also have a hard time believing they are LSD since I generally have to top them off when I don't use them for more then a few days.This is the closest I found:http://data.energizer.com/pdfs/nh15-2000.pdf

author: Nick1296
author_rank: Contributor
timestamp: March 30, 2017, 05:32:02 pm
content: Quote from: IanB on March 30, 2017, 05:16:31 pmI would guess the meter doesn't draw a lot of power when you use it with the data logging function turned off. I could reasonably see higher power draw when the data logging is turned on, so there's that.

author: james_s
author_rank: Super Contributor
timestamp: March 30, 2017, 06:15:45 pm
content: Quote from: IanB on March 30, 2017, 05:16:31 pmI think the main advantage is very long shelf life, they are probably good for emergency flashlights and such, like one kept in the car. For high drain applications NiMH wins hands down, you can simply recharge it, the cost will be *far* lower, they will pay for themselves and the charger after just a few cycles.

author: Nick1296
author_rank: Contributor
timestamp: March 31, 2017, 12:30:15 am
content: Quote from: james_s on March 30, 2017, 06:15:45 pmFrom what I understand, those are the only two situations where Lithium makes a easily noticed improvement.

author: IanB
author_rank: Super Contributor
timestamp: March 31, 2017, 01:11:20 am
content: Summarizing the advantages of lithium primary cells:1. They are very light, weighing much less than other cells2. They have a long shelf life, good for backup use3. They have a high power output4. They do not leakDisadvantages:1. They are expensive2. The higher voltage (of the AA and AAA replacements) may upset certain items not expecting it

author: David Hess
author_rank: Super Contributor
timestamp: March 31, 2017, 03:09:35 am
content: Quote from: Nick1296 on March 30, 2017, 03:51:11 amLiFeS2 AA cells do not even have double the capacity of alkaline cells so they are less cost effective than cheap alkaline cells in low discharge applications.

author: joeqsmith
author_rank: Super Contributor
timestamp: March 31, 2017, 03:31:31 am
content: Quote from: Nick1296 on March 30, 2017, 03:51:11 amThat meter survived all of my testing with the new generator. It also has the largest 10A current shunt I have ever seen in a handheld meter. Hope you enjoy it.

author: Nick1296
author_rank: Contributor
timestamp: March 31, 2017, 08:31:49 pm
content: Quote from: joeqsmith on March 31, 2017, 03:31:31 amYeah, I'm impressed for what I paid for it ($61.59). I'm also a little surprised they did a good job with this one, since I had the 2200075 a few years ago, which was returned since the 10A jack separator cracked. It was probably fine, but that was ridiculous.At this point, I think the 2200075 and 2200813 are just bad meters. I wouldn't recommend those two because the plastic on the jacks is terrible (I had the 2200075). I believe the only difference between the two versions of the last meter I got from them is the 813 is Averaging with a battery tester and the 075 loses the battery tester for True RMS. The function count is also different between the two. They both share the stupid idea of a unfused 10A jack, though. You'd think they'd fuse the 10A on the True RMS variant, at least.