Energizer Ultimate Lithium: sudden failure of only some cells - Page 1
Forum section: electronics / projects

author: 6SN7WGTB
author_rank: Regular Contributor
timestamp: September 21, 2024, 08:31:16 am
content: (There's a thread entitled Asymmetric Battery Drain - appears similar but 7 years old)I have a SONY radio that uses 4 AA cells in series. There obviously is a quiescent drain as a LCD clock is run when 'off' - and I've measured it as 0.15mA.The radio is used occasionally - where this may be 6 months between uses.The issue is that I find although the LCD is usually alive, the radio proves inoperative as SOME of the Energizer Ultimate Lithium cells are completely dead - i.e. down to mV levels. The remainder are as good as new.Yesterday as an example, LCD and clock correct, but radio dead when turned on. Removed the 4 AA cells, and two were 1.73V and two were sub 1mV.The two new replacements I installed were 1.74V. So the two 'good' ones left were indeed as good as new - I wrote the date on as May 2024 (on all four originals).This has happened at least three times in the past 5 years.Now on this occasion the two duff ones were a different batch number, BUT in the past I have had this with some from the same batch, so the issue is repeatable and not confined to one batch.Any thoughts?

author: mikerj
author_rank: Super Contributor
timestamp: September 21, 2024, 09:00:41 am
content: Does everything in the device use the full voltage of all four cells? I have seen poorly designed products that tap off lower voltages from the battery, giving higher drain on some cells.

author: MK14
author_rank: Super Contributor
timestamp: September 21, 2024, 10:51:53 am
content: Quote from: 6SN7WGTB on September 21, 2024, 08:31:16 amQuote from: mikerj on September 21, 2024, 09:00:41 amMaybe the LCD clock, runs from 3V, from just 2 of the AA batteries, as first hinted at, by the second post, I quoted (6V could be too high for that part of the circuitry and/or increase the quiescent current, by a fair bit, probably double).Is the '0.15mA' quiescent current, coming from all 4 batteries, or just two of them? (presumably the ones which end up at near 0 volts, eventually).

author: 6SN7WGTB
author_rank: Regular Contributor
timestamp: September 21, 2024, 02:34:31 pm
content: The batteries are all in series with no taps.I have the factory schematics plus a fairly deep knowledge of the unit as I have done the full SMD re-cap...

author: voltsandjolts
author_rank: Unknown
timestamp: September 21, 2024, 02:47:32 pm
content: Well, you're not alone!https://www.eevblog.com/forum/renewable-energy/sudden-death-problems-with-energizer-ultimate-lithium/

author: 6SN7WGTB
author_rank: Regular Contributor
timestamp: September 21, 2024, 03:01:37 pm
content: Hadn't spotted that - would have appended. Sorry.But, yes, precisely the same issue - virtually unused cells will collapse suddenly.

author: MK14
author_rank: Super Contributor
timestamp: September 21, 2024, 03:10:59 pm
content: Quote from: voltsandjolts on September 21, 2024, 02:47:32 pmThis:https://data.energizer.com/pdfs/lithiuml91l92_appman.pdfMight explain it, because it seems to say that open circuit batteries (but exhausted, run down ones), can read as high as 1.69 volts (plus any meter reading error). Which can give the illusion, that a set of exhausted batteries, might appear to be ok, with some reading near 0 volts and others reading, perhaps 1.73 Volts (assuming it is not a very high accuracy meter).I.e. specifically, this bit:QuoteEdit: Corrected technical error

author: 6SN7WGTB
author_rank: Regular Contributor
timestamp: September 21, 2024, 03:55:53 pm
content: Not sure I follow: my two exhausted' ones read mV range and the two 'good' ones read 1.74V.If I perform a 1W discharge test, either of the remaining two 'good' ones perform as expected, and in fact identically to two unused ones out of a different batch packet.In other words the two 'good' ones are not on any sort of cusp of being worn out.

author: MK14
author_rank: Super Contributor
timestamp: September 21, 2024, 04:04:26 pm
content: Quote from: 6SN7WGTB on September 21, 2024, 03:55:53 pmUnfortunately, I don't think the test you just described is valid.That battery type, seems to hold up its output characteristics, for a long time, even if fairly run down, see datasheet for better details.So all you might be seeing, is differences between the capacities, of brand new batteries.I.e. Perhaps they are all exhausted, but some totally, and others have enough of a small percentage of life left, to 'appear' to still be good.

author: 6SN7WGTB
author_rank: Regular Contributor
timestamp: September 21, 2024, 04:28:25 pm
content: I suppose to justify my point I need to run the two remaining good ones on a 1W drop test and see how long they take to die.If, following your prognosis, it is pretty quick (indicating they were, as you suggest at the point of dying) then yes all four were statistically around the same.If, however, they last any appreciable time, then something was wrong.And I reiterate all four went in at the same time and have had barely any use at all. Maybe an hour at lowish drain.

author: MK14
author_rank: Super Contributor
timestamp: September 21, 2024, 04:36:18 pm
content: Quote from: 6SN7WGTB on September 21, 2024, 04:28:25 pmIf you can accurately read the battery voltages (while open circuit), the datasheet seems to give, indications of how much life is left in the battery.I've used bold, to try and show the specific sections.QuoteSo, it seems to indicate that batteries (open circuit, and when not had any significant current flow for a long enough rest/recovery period).Will give around 1.8 volts (or more) when new (fresh), and around 1.7 volts (less) when exhausted (fully used up). Please see datasheet for much better and more accurate details, about it.Edit:It seems (to say) that > 1.74 volts (assuming an accurate enough meter), means the battery is 'good'.

author: MK14
author_rank: Super Contributor
timestamp: September 21, 2024, 04:57:59 pm
content: Quick back of envelope calculation.Let's say, you put in 100% brand new/fresh batteries at the start.Quote from: 6SN7WGTB on September 21, 2024, 08:31:16 amIf you still had the original batteries, the drain would be (approximately):Quote from: 6SN7WGTB on September 21, 2024, 08:31:16 amSo, hours in 5 years x current drain = 43,800 (Hours) x 0.00015 (Amps) = 6.57 Amp Hours.Which (if they had been Alkaline batteries), would have needed a few or more sets of them, I suspect.I'm not sure how many sets of those Energizer Ultimate Lithium, would be needed, for such a modest (but significant) drain current.But perhaps 2 or 3 sets, maybe ?EDIT:A quick google search, seems to have google (quick reference), saying:2900 mAh, as their capacity.Assuming perfectly ideal batteries (which I doubt, I suspect such a low discharge rate, hurts the total capacity over time).Then 6,700 / 2,900 = about 2.3 sets.So perhaps (and because you mentioned some rare use of the radio), 3 sets needed, including the first set at the start.Source:https://gogreenbatteries.co.uk/energizer-aa-ultimate-lithium-batteries-l91-lr6-4-pack/Quote

author: 6SN7WGTB
author_rank: Regular Contributor
timestamp: September 21, 2024, 06:10:47 pm
content: The current set went in on 24th May this year, and looking back have had maybe 1 hour use.

author: MK14
author_rank: Super Contributor
timestamp: September 21, 2024, 06:15:00 pm
content: Quote from: 6SN7WGTB on September 21, 2024, 06:10:47 pmAssuming you replaced the entire set of 4 batteries[EDIT: Confirmed, earlier in the thread], all at once then.Were the old capacitors, already all replaced by then?Old capacitors can start to waste current, especially if given too high a voltage, as the battery pack is supposed to be 6 volts, but these seem to give up to around 4 x 1.83 V = 7.32 Volts, which is slightly more likely to be closer to the limit, especially on aging capacitors.EDIT2: There is something funny going on, because if they got used in about 4 months, you would have needed something like 15 new sets by now. So, that is strange.I'm not sure what has changed over the last 5 years for you. But things like unexpected increases in current consumption (of the radio, while off), faulty/fake/cloned batteries, and other possibilities. Come to mind.EDIT3: Anyway, sorry, I've been going round in circles, and not solved your problem. I hope you get to the bottom of this issue. I'd be interested to know, WHY, as well.

author: KE5FX
author_rank: Super Contributor
timestamp: September 21, 2024, 08:27:43 pm
content: They must've gotten a bad batch of PTCs. Or there's a production issue causing them to be assembled improperly. These batteries are normally pretty great.

author: Peabody
author_rank: Super Contributor
timestamp: September 21, 2024, 09:07:39 pm
content: Can you clarify - do the bad cells still pass current? In other words, if the setup is 2S, when one goes completely bad, is the resulting 2S OC voltage now 1.8V, or millivolts? And if it's 1.8V OC, is it still good current under load?To me, the failed cell going to millivolts strongly suggests failure of a protection circuit.I wonder if there's any way to send a failed cell to Energizer, and get a report back of what went wrong. Probably not, unless one of them is lurking here.

author: coppercone2
author_rank: Super Contributor
timestamp: September 21, 2024, 11:35:06 pm
content: I had those cells short circuit and stay 70C for hours this year.It was in a wireless mouse. I almost feel like they don't like RF circuits or something.If you take it apart its pitifully made (dangerous to do, don't), compared to a "good" lithium primary cell like a CR123 cell., as in very thin. They make me a little nervous. The CR123 cell (stubby lithium primary) has very thick separators and internals. The AA primary cell is like ULTRA thin membranes. They are just not durable by design.When they short out, they read very low voltage. It was probobly hot as hell for a while before you opened it too! I put mine in a metal bowl as soon as the mouse broke, and it was literary at a elevated temperature for over 2 hours!!! (70C). Afterwards it was like 10mV after it cooled downSeriously a CR123 cell is mil spec almost, the AA lithium (different chemistry) is like worse then rice paper!!!

author: MK14
author_rank: Super Contributor
timestamp: September 22, 2024, 08:37:02 pm
content: Quote from: coppercone2 on September 21, 2024, 11:35:06 pmThanks, that is interesting.Do you think that what you had, were perhaps fakes (or similar)?Alternatively, do you think that Energizer have moved to a new manufacturing technique/plant/country etc, possibly to save money on production costs, which has dramatically reduced the quality and reliability, of the batteries?Or perhaps some other explanation?The datasheet, does seem to indicate that the cells have a built in safety vent (a quick glance, seems to indicate, it may operate, if the cells overheat). So, the designers, do seem to be expecting the possibility, that cells can sometimes go faulty and need to release, pressurized gases, inside, in a relatively safe way, compared to a possible explosive over-pressure situation, rupturing the cell.

author: coppercone2
author_rank: Super Contributor
timestamp: September 22, 2024, 09:15:44 pm
content: their cheap asses, they are in death struggle over price/quality area of market with the other big ones, there is always some crap going on with those companiesits like TI and AD, but they fight over 0.0001 cent components (billions scale). They arehostileto each other. Frequent lawsuits.

author: Paul T
author_rank: Regular Contributor
timestamp: September 23, 2024, 12:55:44 am
content: This might be a mechanical issue instead of an electrical or chemical one. These cells are typically physically longer than alkaline cells. This could lead to one of at least three problems as they fit tighter in the bay.#1. The crimped edge of the case of the cell presses against the + terminal enough to short or leak through the wrapper end.#2. The higher force at the + terminal causes physical damage to internal construction, or activate a pressure safety device inside under the terminal cap.#3. The cell moves sideways under force, causing some sort of a short between the adjacent cells, depleting one due to case contact.When the spring is too long on the negative terminal, one could cut down some of the coils to reduce the force. I’ve needed to do this to some of my devices in order to enable fitting Eneloops or Lithium cells.EDIT: I just measured the resistance along the wrapper edge with sharp gold-plated test leads, tips spaced about 1mm apart. The resistance was 160 megohm.Under a microscope, it looks like the core of the wrapper is a plastic, and the top and bottom surfaces are metallic coated, then an adhesive. Maybe someone could do a more extensive study of the wrapper materials.Considering the skin of the wrapper is mildly conductive, the problem may be due to adjacent cell's cases or wrappers in physical contact as they probably alternate directions in the bay.Also suspect is the region of the wrapper leaving the (-) side of the case up around and onto the (+) terminal. If the mating terminal in the device's battery bay is pressing against the wrapper near the (+) terminal of the battery, it could cause an electrical short/leak because the adhesive is displaced and the wrapper touches both conductors.Can you inspect your bad cells for evidence of physical contact against the wrapper? Might be worth tracking which physical position the failed cells were place.I have been 100% pleased with lithium primaries from Energizer in all sorts of devices. I have never had one drop voltage when not in service. I've been using them over 25 years. No explosions, no leaks, nothing bad ever happened at all.

author: Paul T
author_rank: Regular Contributor
timestamp: September 23, 2024, 02:14:01 am
content: Quote from: MK14 on September 21, 2024, 03:10:59 pmThanks for this, really good information. This document also states in the precautions:"Battery labels insulate the battery to reduce the incidence of a potential direct short circuit or inadvertent charging. Battery compartment contacts and welded tab connections must not have sharp edges/burrs that could cut through the battery label especially adjacent to the positive terminal."Similar to what I'm talking about, stated a different way.

author: MK14
author_rank: Super Contributor
timestamp: September 23, 2024, 11:24:59 am
content: Quote from: Paul T on September 23, 2024, 12:55:44 amThanks. That makes sense.I find it annoying, that the exact dimensions of AA batteries, is either not too well bolted down, or not respected by all parties involved.There seems to sometimes be similar issues, with 9V PP3 batteries. Because the lithium very long life versions of these, either doesn't always fit, or is a rather tight one.Even if you are the actual manufacturer of these batteries. It can be very difficult, to find out, what the real causes of these issues, really are.E.g. The exact batch code(s) are usually not specified in internet claims of faulty batteries. Were they really fakes, abused, faulty equipment, misused, or is it a fake review, sponsored by a competitor etc.Some people have noted in this thread that the near 0 Volts, of the suspect cells, is rather suspicious (or a fault rather than excessive current drain, from the device). On reflection, I now agree with them. Because (although I usually get involved with other battery types), batteries do seem to nearly always have some kind of terminal voltage, even if it is only a few hundred millivolts, or even slightly negative, in some rare cases (usually when multiple batteries are involved and big current draws from the device, with no automatic switch off, when the voltage is too low).I assumed, it was because the battery got reverse charged and went internally short-circuit, or something, because of the multiple batteries, and permanent 0.15 milliamp drain, from the LCD clock, in the OP of this thread.Given that AA rechargeable batteries, can (if you get the right, quality types), keep most of their charge for 5 or even 10 years, shelf-life, and can be readily reused (recharged). Have a good reputation for being leak-proof (assuming you stick to the top/best brand(s) ). Have capacities of 2,000 milliamps (and 2,500 milliamps, but shorter self discharge rate, of something like 3 years, which would be fine, for most applications). I'm not sure why people would be attracted to these one-use lithium batteries.Unless it was an extremely valuable, vintage device (so near zero leakage risk is wanted), or the higher (perhaps 2,900 milliamps), and extremely long shelf-life (I think it is 20+ years), wanted/needed.I have noticed, many people, are completely uninterested in recharging batteries, and have got many more important things to worry about in life, so I will try and not preach here (as I probably use more AA Alkaline batteries, than I should/need, save the planet wise, that is).

author: Paul T
author_rank: Regular Contributor
timestamp: September 23, 2024, 11:37:40 am
content: Sometimes NiMH cells are too heavy, too low voltage, too large, or require disassembly to get to. In digital cameras lithium primary longevity and light weight is unmatched. I also use rechargeables every place I possibly can. I also consider device conversion to lithium rechargeable when appropriate. Follow my signature like where I have shown a few examples of how this can be done and why.As for size, I believe there are long standing tolerances for acceptable dimensions. To maximize capacity and incorporate safety features, these cells push it to the upper boundary and maybe a little over. I suppose we as consumers may be partly to blame.I continue to suspect the OP's issue is shorting or electrically leaking, due to to some combination of the battery bay conductor geometry, the cell adjacency, the cell size, and the slightly conductive layers in wrapper. I agree that a reverse charged cell would not be almost exactly zero and never negative.

author: Jeroen3
author_rank: Super Contributor
timestamp: September 23, 2024, 12:04:37 pm
content: When this happens with normal alkalines they can give you a negative open circuit voltage.Do these batteries act much different?

author: Peabody
author_rank: Super Contributor
timestamp: September 23, 2024, 02:18:18 pm
content: One reason to use these batteries is they work well over a wide temperature range. If you use rechargeable lithiums outdoors, you can't charge them in freezing weather, so things become complicated. Alkaline and NiMH don't deliver well when really cold.Is there any known history of these batteries being dead right out of the package? If not, then the explanation of physical distortion when inserted into the holder would seem to be pretty likely.

author: MK14
author_rank: Super Contributor
timestamp: September 23, 2024, 06:06:26 pm
content: Quote from: Paul T on September 23, 2024, 11:37:40 amYou're right!I've made a partly foolish post, earlier in this thread, I should have remembered about their (NiMh rechargeables) limitations, such as lower cell voltage. Which can make them unsuitable for some applications. Thanks for correcting me.Also, many, many years ago (including previous NiCd types), they had other issues. Such as, slow to recharge (the old ones), memory effects, could dramatically leak, damaging/destroying vintage PCBs, when decades old, potentially toxic.But one of the main pains with them (the really old ones, even when they were new/current), is they would somewhat rapidly self-discharge, even when not used. Supposedly, they could keep their charge for a few months, but in my experience older (especially well used cells), could discharge, in as little as a month (maybe even a fair bit less than that).Their capacities, used to be fairly poor as well, perhaps 450 milliamps (IIRC), for an AA cell.Although, at such time periods (many decades ago), the common battery type, the Zinc/Carbon cells, didn't have good capacities, were relatively weak, would readily leak, and could (it varied between brands, sizes, uses and luck etc), have rather poor shelf lives. But in some amazing cases, could carry on (e.g. in some Casio calculators), for many decades and longer, somehow.

author: MK14
author_rank: Super Contributor
timestamp: September 23, 2024, 06:13:32 pm
content: Quote from: Peabody on September 23, 2024, 02:18:18 pmYes (big temperature range, for the Lithium batteries, in the OP), I'd forgotten about that, even though I had only just very recently read about it, in the datasheet.Which makes them more versatile and useful, when outdoor low temperatures and other situations, need that capability.Also, good point about the physical distortion (as also mentioned by other(s) ).

author: Paul T
author_rank: Regular Contributor
timestamp: September 28, 2024, 11:28:02 am
content: Another thing to consider is theopposite case polarity on lithium cells.The entire can and crimps of an alkaline is the +anode except the very center of the bottom flat.The entire can and crimps of a lithium cell is -cathode except the very center of the top nipple.The + terminals of the battery bay was probably designed with alkaline cells in mind. If alkaline cells are used, any flaw in that design which touches the case or presses on the wrapper anywhere along it's length will not cause an electrical short or leak, because it is the same electrical connection as the nipple.The user manual might even tell you to use alkaline cells. By putting in physically long lithium cells with reverse case polarity, the manufacturer might consider that action "at your own risk".To get around the risk,it's up to the user to take the extra steps to assure the entire cell body is completely isolated from the +terminal. Also, to protect cells from touching each other in a side spaced close-proximity alternating series arrangement.EDIT: Add picture of a + terminal that could by risky when lithium type cells are used.I don't know why Energizer has to make use of a metallic wrapper which ends up being partially conductive along the surface(s). It's a recipe for high resistance electrical shorting as previously described.

author: 6SN7WGTB
author_rank: Regular Contributor
timestamp: February 11, 2025, 07:43:53 am
content: Late back to this.Just to confirm one point - the cells are at no risk of any sort of short, or tight connection. See example below.Opening the radio today, all four batteries currently fitted are 1.73V. Not done any drop or load tests yet.