Batteries for handheld test gear. - Page 1
Forum section: electronics / testgear

author: BillyO
author_rank: Super Contributor
timestamp: June 24, 2023, 12:10:53 am
content: Does anyone have experience with those rechargeable 9V lithium batteries in handheld test gear?They seem to have up to twice the capacity (maybe false claims) of alkaline cells, much reduced chance of leakage and potentially much, much longer life.I'd be very interested in any and all thoughts/experience.How long do they actually last between charges, how quickly do they re-charge, what is their self-discharge rate ... ?

author: beanflying
author_rank: Super Contributor
timestamp: June 24, 2023, 01:04:07 am
content: Lithium batteries in general have little self discharge so way better than Nickel chemistry.** Need to be careful depending on the actual chemistry of the Lithium in the case of 9V nominal generally they use 2 cells so 8.4V fully charged (a bit under 8V for a lot of their capacity) but if it is a Phosphate cell then I have seen 3 x 3.2V (9.6) volts fully charged. There is as an example an issue with the 121GW meter (AA's) and these causing issues with it.Some of them run onboard chargers and will be 1-2 hours looking at a couple of rubbery specs. 5V USB input at 1A maxAs you are waving a Canadian flag too Lithium batteries fall off a cliff when you get cold so factor that in too.

author: nctnico
author_rank: Super Contributor
timestamp: June 24, 2023, 01:07:16 am
content: Quote from: beanflying on June 24, 2023, 01:04:07 amYep. Try to use a photo camera that has a lithium battery at -10... It doesn't work well.

author: BillyO
author_rank: Super Contributor
timestamp: June 24, 2023, 01:17:32 am
content: Quote from: beanflying on June 24, 2023, 01:04:07 amThanks for your input.I'm in an all modern heated home, not a igloo in Nunavut?

author: wasedadoc
author_rank: Super Contributor
timestamp: June 24, 2023, 01:29:41 am
content: I've never experienced leakage from 9 Volt alkaline, 6LF22 size batteries. Yes from alkaline AA and AAA cells.

author: BillyO
author_rank: Super Contributor
timestamp: June 24, 2023, 01:33:54 am
content: Quote from: nctnico on June 24, 2023, 01:07:16 amThere's a trick to that. My other hobby is nature photography.https://www.dreamstime.com/omegamic_infoFor early spring, late fall and winter I have a small pouch I wear around my neck that hangs in my armpit. In there I keep two spare batteries and rotate them through as required.

author: BillyO
author_rank: Super Contributor
timestamp: June 24, 2023, 01:37:46 am
content: Quote from: wasedadoc on June 24, 2023, 01:29:41 amThat's just one concern. My main goal is to reduce costs and waste, if possible. A good alkaline costs more than $2 a piece. The rechargeable I've been looking at are about $6. If they last 4 0r more times longer than alkaline cells they are good to go.

author: helius
author_rank: Super Contributor
timestamp: June 24, 2023, 01:58:58 am
content: 9V alkalines definitely do leak, but the construction helps to limit the damage. You can cut through the outer casing to reveal 6 alkaline cells each having their own case. This makes it harder for leaked electrolyte to spill into equipment, although the battery can get quite puffed and furry.

author: Fungus
author_rank: Super Contributor
timestamp: June 24, 2023, 02:44:38 am
content: I use rechargeable 9V in my Brymen, never had any problems.

author: AVGresponding
author_rank: Super Contributor
timestamp: June 24, 2023, 08:20:44 am
content: I use a PP3 Li-ion in my PP3 meters, it works fine. The only downside is that because it uses a single cell and a boost converter, it outputs a constant 9V throughout its discharge cycle, so you don't get a low battery warning from your DMM. They last months though, so it's not a serious problem, for me anyway.

author: J-R
author_rank: Super Contributor
timestamp: June 25, 2023, 04:31:33 am
content: Typical lithium-ion 9V batteries that leverage two pouch cells in series plus a BMS circuit are about 600mAh, which is very similar to alkaline under low-discharge rates (10mA or so).Of course alkaline has the known weakness of losing lots of capacity when consumed at higher rates. So any comparisons will depend on the equipment they are installed in.Lithium-ion 9V batteries that claim higher capacities are just lying, and some are much lower in practice. IMHO based on the volume the most you could hope for in the PP3 form factor after eliminating any circuitry would be maybe 750mAh.EBL has been mentioned as a reasonably good brand. I purchased four direct and one has gone bad after a year, however.

author: AVGresponding
author_rank: Super Contributor
timestamp: June 25, 2023, 07:25:34 am
content: Quote from: J-R on June 25, 2023, 04:31:33 amDid you return it under warranty, or tear it down to investigate?

author: alm
author_rank: Super Contributor
timestamp: June 25, 2023, 10:10:08 am
content: I use low self discharge NiMH batteries in battery powered test equipment like DMMs. The 9V models won't have the capacity of Li-Ion batteries, but are much simpler and last plenty long with low power draw (10mA is not low for a 9V battery) handheld equipment.For very low draw equipment I use primary lithium batteries.

author: iJoseph2
author_rank: Regular Contributor
timestamp: June 25, 2023, 10:53:44 am
content: I've been using these in my Fluke 70 series meters...https://lygte-info.dk/review/batteries9V/Soshine%209V%20LiIon%20650mAh%20(White)%20UK.htmlProbably ordered from here ...https://www.aliexpress.com/item/32808238857.htmlIt's been about 2 years since I installed them .. which reminds me I should probably at least have a look at them physically.

author: BillyO
author_rank: Super Contributor
timestamp: June 25, 2023, 02:02:02 pm
content: Quote from: iJoseph2 on June 25, 2023, 10:53:44 amWhat do you use to charge them?

author: J-R
author_rank: Super Contributor
timestamp: June 26, 2023, 03:23:10 am
content: The failed EBL would only charge to approximately 8V, then it would disconnect. Working units disconnect at just above 8.4V.After disassembly, I found one cell at 3.8V and the other at 4.2V.

author: AVGresponding
author_rank: Super Contributor
timestamp: June 26, 2023, 05:21:06 am
content: Quote from: J-R on June 26, 2023, 03:23:10 amThe Znter brand ones have a single cell; Big Clive has taken one apart. It's quite disappointing that the EBL one can't balance its cells properly, is there a charge controller, or are they relying on individual cell protection boards to just cut them off at 4.2v?

author: Berni
author_rank: Super Contributor
timestamp: June 26, 2023, 05:45:16 am
content: Yep Lithium cells are a good idea.I use the "Philips Lithium Ultra" cells in my DMMs. They do last longer, but the difference in capacity is i think about 2x while they cost 3x. So they are not really a way of saving money, especially if you compare them to the cheep store brand alkaline cells. But the AA cells last a really long time in a DMM so i don't care about the extra cost. The real reason i do it is that they never leak. The DMMs are rather expensive so i am willing to pay extra for a battery that will not destroy it by barfing electrolyte all over its insides.Alkaline cells leak no matter what the brand, even ones that claim "Anti leak" on the package. Some brands are significantly less leak prone than others, but they still leak if you are unlucky enough.If the goal is to save money they go for rechargeable Ni-MH. The modern ones have self discharge rates low enough to be usable for this and after a dozen or so recharges they will pay for themselves in not needing to buy new batteries. The capacity does take a hit, but then again the battery life of 9V powered DMMs was never that great to begin with anyway (that's why all of mine are AA or AAA now).

author: iJoseph2
author_rank: Regular Contributor
timestamp: May 06, 2024, 04:39:43 pm
content: Quote from: BillyO on June 25, 2023, 02:02:02 pmHi @BillyO, apologies for not getting back .. I completely forgot I posted that and been far too busy working.Originally I got a soshine charger with them and used that at first, but then I saw a youtube video about them potentially killing the internal BMS circuit .... so got a Nikon battery charger and fitted a 9v clip .. then realised 550mA (about 1C) is probably too much for these, so got a lower current (120mA) Nikon charger (yet to be modified).Until I sort that out I've been using a bench power supply limited voltage to 8.0 to 8.4v (depending how full I want them) and current limited to 100mAJoseph

author: iJoseph2
author_rank: Regular Contributor
timestamp: May 06, 2024, 04:50:47 pm
content: I've noticed Soshine have updated their stock ..The last one is probably one 1000mah 3.7v cell hence the bigger number.680mAh:https://www.aliexpress.com/item/1005005544326394.html500mAh USB:https://www.aliexpress.com/item/1005006240308560.html1000mAh USB Constant Volt:https://www.aliexpress.com/item/1005005921997945.html