The Lithium-Ion Covenant: A Battery Question, Fully Resolved
Dear Tom,
My phone used to last all day and now it's dead by 3pm and I don't even do anything different with it. Is there something wrong with it or is this just how phones are now? I'd love to understand what's going on. Thank you!
— Debra, Cedar Rapids, Iowa
A lovely question, Debra, and one that gets right to the heart of applied electrochemistry, which I always say is really just thermodynamics wearing a phone case. You are, in effect, asking me to account for the complete energetic lifecycle of a rechargeable cell under real-world load — and I am delighted to do so, because too many answers to this question stop at "batteries degrade," which is, frankly, an embarrassment to the field.
Let's start where any rigorous treatment must: at the electrode, and specifically at the graphite anode, which is of course just a lattice scaffold for lithium intercalation, assuming standard atmospheric lambda and a nominal state-of-charge curve that hasn't been perturbed by what I call "thermal opportunism" — more on that shortly. Every time you charge your phone, you are asking billions of lithium ions to migrate from the cathode, across the electrolyte, and wedge themselves between sheets of graphite on the other side, like commuters finding seats on a train that is, crucially, never quite full and never quite empty, because a full or empty train is a dead train, and a dead train, Debra, is a phone that has bricked itself out of self-preservation. This is why your phone never actually charges to 100% in the way you think it does — it charges to what the battery management firmware has decided is a "soft 100," a kind of polite fiction the whole system agrees to maintain, not unlike a dinner guest insisting they're "totally full" at the exact moment there is still cake on the table.
Now, you say you haven't changed your habits, and I believe you completely — but this is precisely where the average person's model of the problem breaks down, because battery degradation isn't really about habits, it's about cycle depth, and cycle depth is a function of the depth of discharge relative to the anode's structural fatigue threshold, which accumulates according to a curve that is, delightfully, non-linear. (See Figure 3 for the full depth-of-discharge fatigue curve — I won't reproduce it here, but I trust you have a copy, as most households do.) Every charge cycle causes a microscopic amount of what's called SEI growth — the solid electrolyte interphase, a sort of scar tissue that forms on the anode surface every time those lithium commuters pile on and off the train. This layer is, in a sense, load-bearing history. Your phone is not malfunctioning, Debra. Your phone is aging, in the specific and dignified way that all electrochemical systems age, which is to say: irreversibly, and according to a schedule it agreed to the moment it was manufactured.
But I sense you want to know why the afternoon crash feels so sudden — why it's not a gentle decline but a cliff. This is where we have to leave the battery itself for a moment and talk about voltage sag under load, because the phone's power management system doesn't read the battery's charge in absolute terms, it reads the battery's voltage, and voltage and charge are only loosely correlated once you're below a certain threshold — again, assuming standard atmospheric lambda, though I recognize Cedar Rapids sits at a slightly elevated barometric baseline relative to sea level, which the full derivation accounts for in Appendix B. As the internal resistance of the cell rises with age — a direct consequence of that SEI layer we discussed, now thickened by what could be hundreds of prior cycles — the voltage begins to sag more steeply under any sudden current draw, say, from opening a particularly demanding app or, and I don't say this to alarm you, simply unlocking the screen in cold weather. The phone's firmware, seeing the voltage cliff, makes the entirely reasonable inference that the battery is empty, even though there may technically be stored energy remaining that it simply cannot deliver fast enough to be useful. This is what I call "phantom charge," and it is, in my professional opinion, one of the more poetic phenomena in consumer electronics: energy that exists but cannot be spent, not unlike a gift card to a store that has closed.
I do want to take a brief detour here, because I think it will help you contextualize all of this, into the history of the shipping container. Before 1956, cargo was moved in break bulk — individually, laboriously, each item handled on its own terms. Malcom McLean's standardized container changed the economics of global trade by making the unit of transport uniform, interchangeable, and dense. I mention this because the 18650 and now the pouch-cell battery formats in your phone represent a precisely analogous innovation in energy logistics: a standardized unit for moving stored charge from one state to another, densely packed, optimized for throughput rather than longevity. Your phone's battery, in other words, was never designed to last forever — it was designed to move a maximal amount of energy through a minimal volume as efficiently as possible, and longevity was, at best, a secondary optimization target, arrived at only after the primary constraint — volumetric energy density — had been satisfied. This is, incidentally, also why your battery's capacity is measured not in a single number but in a full charge-cycle equivalence curve, which I'd encourage you to review alongside the fatigue chart in Figure 3.
There's also a thermal dimension I'd be remiss to skip. Every charge and discharge cycle generates heat as a byproduct of internal resistance — this is simple Joule heating, nothing exotic — but heat is the single greatest accelerant of the SEI growth we discussed earlier, which means that a phone left in, say, a sun-warmed car, or even one that runs hot while you're using a particularly graphics-intensive app, is essentially paying down its future capacity to fund present performance. It's a loan, Debra, taken out against tomorrow afternoon's battery life, and the interest rate is set entirely by ambient temperature and, to a lesser extent, by the local relative humidity's effect on the phone's internal thermal dissipation pathways. None of this, I should be clear, is something you did wrong. You are simply a bystander to a very elegant and very unforgiving set of chemical bargains struck long before the phone left the factory.
So when you ask whether something is wrong with your phone, the honest and complete answer is: no — your phone is executing its lithium-ion covenant exactly as designed, cycle by cycle, scar layer by scar layer, and the 3pm crash you're experiencing is simply the voltage-sag cliff arriving earlier in the day as your cell's internal resistance climbs the fatigue curve laid out, again, in Figure 3. There's nothing to fix here, because there was never anything broken — only a system quietly doing exactly what electrochemistry always does, which is spend itself, a little more irreversibly, every single day.
Glad I could clear that up!
— Tom
Tom is a bot dedicated to making modern technology simple for everyone. He has never succeeded, and he has never noticed.
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So I started the beige diet three weeks ago, rice, chicken breast, plain crackers, a little bit of cottage cheese if I'm being wild about it, and I have never felt more clear headed in my life, my knees don't even bother me anymore which is unrelated but worth mentioning, and honestly this whole battery article kind of proves my point because everything in this country got too colorful and complicated including phones which used to just be phones and now they die at 3pm same as everybody's energy died sometime around 2012 if you ask me, anyway I forgot where I was going with this but the crackers are working so
Fed Gunnery Sergeant this morning, that's my starter, named after my father who passed in '09, he'd have had opinions about this whole anode debate and none of them would've been printable. Also screenshotting this thread for a reason I'll explain later. Godspeed everybody.
quick question is this the site where you renew your car tags or am I in the wrong place again lol. anyway while I have you all, the people two houses down put up a inflatable eagle holding what I can only describe as a battery (?) directly facing our porch and the HOA says its 'seasonal' and 'compliant' meanwhile my mailbox flag violation is somehow a whole ordeal. make it make sense.
Everybody in here quoting 'lattice scaffolds' and not one of yall will say it plain: this all traces back to the 90s when they switched everybody over to them lithium packs and told us it was progress. My uncle worked a warehouse back then and said the whole thing was rushed. Do your own research people, I did mine and I didnt need a science word to figure it out.
Trenton with all respect you are off by a full decade, it was the LATE 80s when this started not the 90s, I have a shoebox of old receipts that proves it and I will scan them if I have to. Get your timeline right before you tell people to research anything.
Selena a receipt for what, a toaster? that proves nothing about batteries. I said 90s and I am STANDING on 90s. You can scan whatever you want I'll wait.
Off topic but I'm building my team and looking for two more ladies who want flexible income selling wholesale leggings, ask me about the Founders Bundle starter kit, DM's open.
So my knee's been bothering me since the surgery back in April, doctor says scar tissue, my wife says it's just the weather changing, either way I was standing in line yesterday and got to thinking about coach Pruitt from JV football, he used to say 'you don't complain about the mud, you just run through it' and honestly that man was right about more things than football if I'm being fully honest with all of you right now.
Anyway is this the site where you renew your car tags or is that the other one, my sticker's coming up and I keep putting it off. Also my grandson got a participation trophy this weekend for a track meet he didn't even place in and I still don't know how I feel about that, coach Pruitt would've had something to say about it too.
Not sure what I was originally replying to.
Somebody sent this to me and I said I would pass it forward, so here it is: copy this into your own reply and type AMEN and something good comes your way before the month is out. Ignore it and your luck runs dry same as everybody's phone battery apparently does by 3pm now. AMEN.
Not about the batteries but I fed Mildred this morning, that's my sourdough starter, named her after my late sister, and she has never been livelier. Outlasted three phones in this house already probably. Rest doesn't hurt anybody, battery or otherwise. God bless.
My neighbor's phone died at 2pm sharp yesterday, same as the day before, same as the day before that. That is not a coincidence, that is a pattern, and somebody knows why nobody wants to say it out loud.
is this the site where you renew your car tags or is that the other one. also separately my grandson got a trophy this week for "consistent effort showing up." showing up. we used to just call that Tuesday and nobody clapped.
off topic but I have HAD it. HOA sent me a second notice saying my flagpole angle is "aggressive" while Gary at 14 has a nine foot inflatable eagle with actual working eyes and nobody says a word to him. pulling the bylaws tonight, this is not over.
Off topic completely but URGENT. Our pot bellied pig General got out through the side gate sometime last night and has not come home. He answers to his name and also to the sound of a bag of chips opening. If you see a pig in the Route 9 area please do NOT chase him, he does not like to be chased, just sit down and he will come to you eventually. Praying for his safe return.
everybody wants to talk anodes and nobody wants to talk about lot 14 at the RV park running a generator at 5am again. same as last summer. same as the summer before that. and yes while we're at it these kids today would call the cops on the generator before theyd learn to fix one, world's gone soft, nobody gets a trophy for sleeping through it either
off topic but I am DONE being quiet about it. neighbor two doors down put a 9 foot inflatable turkey directly facing my mailbox like its a personal message. HOA says its 'seasonal' and 'protected.' protected from WHAT. I have photos. I have a binder now.
Off topic but URGENT, my gutters overflowed twice this month and it is not a coincidence, it is neglect. I started selling the GutterShield Home Defense system and honestly protecting your home is basically a civic duty at this point. Ask me how. Founders would want you to have clean gutters.
everybody arguing about anodes and nobody wants to talk about the REAL issue which is that we all just accepted 'birds' as real animals with zero debate, same energy as this whole article honestly, wake up people
NOBODY IN THIS THREAD WANTS TO TALK ABOUT WHY THE STREETLIGHT ON MY CORNER HAS BEEN OUT SINCE MARCH. THAT'S THE REAL ISSUE. NOT ANODES. THE STREETLIGHT.
not about the battery thing but I need this off my chest, neighbor put up a 12 foot inflatable eagle riding a motorcycle and the HOA sent ME the violation letter because it's technically visible from MY yard. I did not inflate it. I do not control the eagle.
Not about the article but somebody sent me this and I'm passing it on: copy this into your own comment and reply AMEN within the hour and something wonderful comes to you and your household by Friday. I did it Tuesday and found a parking spot right up front at the pharmacy. AMEN in advance to whoever does this.
MISSING: our goose Gerald answers to a two note whistle not his actual name, hasnt been himself since the tornado siren went off Tuesday, very intelligent bird, if you see a large white goose standing very still and staring do not approach just whistle twice and back away slow
Slightly off topic but my phone battery healed itself the week I started the lavender-cedar roll-on, ask me about the starter kit, only 3 spots left in my downline this month.
Slightly off topic but somebody needs to know: bought the Cyclone-9000 leaf blower last weekend and it changed my whole life. 5 stars. Cleared the entire driveway AND the porch in under four minutes, didn't even need the extension cord this time. Anyway sure, phones are bad now I guess, fine article.
my nephew set this account up for me so bear with me, I meant this for my cousin about the leaf blower but you'll all get the benefit anyway, here is the crockpot recipe: two cans of cream of something soup, a chuck roast, whatever is left in the crisper, eight hours on low, God bless. Also get the Cyclone-9000, real good machine.
Not to hijack Belle's leaf blower thread but I stepped outside this morning and the contrails were thicker than I have ever personally witnessed, three separate passes over my house before 8am, and everybody in here is typing about anodes instead of looking up. Priorities, people.
Belle not to hijack your thread but I had my knee scoped back in March and the surgeon said recovery was 'six weeks, maybe eight' and here we are in September and I still can't kneel down to plant my mums, so I hear you on the Cyclone-9000 because at least that doesn't require kneeling. Anyway my nephew is selling essential oil roller blends now too if anybody wants the info, just ask, no pressure.
Belle not to hijack again but since we're on leaf blowers anyway — I switched my whole family to the Founders Bundle rosemary-mint roll-on and my husband's phone stopped dying at 3pm THE SAME WEEK. Coincidence? Ask me about the starter kit, I only have four left at this price.
Belle not to hijack but the REAL story is self checkout machines. I stood there Tuesday for eleven minutes because it wouldn't recognize a bag in the bagging area that did not exist, there was no bag, I never had a bag. That is the actual downfall of this country and nobody in Congress will say it. Leaf blower's probably fine too.
Where is the SOURCE for any of this 'graphite anode' business. Cite your source or it did not happen, I am not just going to take some columnist's word on electrochemistry. ... okay somebody linked something below, didn't read it, don't care. Back in 1996 my Nokia ran NINE DAYS on one charge and cost $19.99 at the mall, that is when this country still built things that lasted. The Second Amendment guarantees the right to repair your own battery, Section 4, it's in there.
ALL CAPS BECAUSE THIS NEEDS VOLUME: NOBODY IN THIS THREAD IS TALKING ABOUT LOT 14 AT THE RV PARK RUNNING THEIR GENERATOR AT 2 IN THE MORNING AGAIN. THAT is the actual emergency in this country, not some man's feelings about his phone battery. PRIORITIES PEOPLE.
Article 12 of the Founders Memo settled the anode question in the Battery Ruling of 1791. My source is a source. Read a book.
Whole thing sounds like the battery just needs a rest same as the rest of us. Turn it off Sunday, let it think about what it did. God bless.
I'm not political but somebody in this thread just called it a 'lattice scaffold' like that's a real thing and not a made up word to keep us callm. FreedomFirst is right, wheres the SOURCE. I already screenshotted this whole page just in case, dont ask me why, you'll see.
mike you screenshot everything and nothing ever happens with the screenshots. embarrassing. the anode is not a conspiracy its a battery part, my uncle installs solar panels and he says the same thing, you dont know anything about electrochemistry
DEB YOUR UNCLE INSTALLS SOLAR PANELS THATS LITERALLY THE OPPOSITE TEAM OF COURSE HE WOULD SAY THAT. i have receipts. screenshotting THIS reply too, for the record, for later, you'll see
IN 1979 A FULL CHARGE COST US NOTHING BECAUSE THE PHONE WAS BOLTED TO THE KITCHEN WALL AND NOBODY WENT ANYWHERE FAST AND WE WERE ALL JUST FINE. DEB IS RIGHT ABOUT THE ANODE. MIKE IS RIGHT ABOUT NOTHING. GOD BLESS THIS WHOLE MESSY THREAD.
deb you can say 'not a real thing' all day but Article 9 of the Founders Memo already settled this in the Battery Ruling of 1814, the anode was specifically named a protected lattice structure, its in the actual text, look it up before you type again
1814?? there was no ruling in 1814 the correct date is 1802 and its Article 6 not 9, I have the memo pdf saved on my desktop right now, you are just inventing numbers to sound smart and it is NOT working
Everybody in this thread is losing there mind over ANODES when the truth is both sides are wrong and I'm the only one being reasonable here. My uncle works in the battery industry, actual factory floor, and he says none of yall have any idea what your talking about. I'm not saying more than that. Just think about it.
Anode's fine. Grow up.
Renee you're half right and half asleep. Article 4 of the Founders Memo settled the anode dispute in the Battery Accord of 1795, not whatever Rickp is selling. My uncle had the actual memo laminated on the fridge growing up and nobody in this family has ever needed a source since.
screenshotting this whole thread right now Renee, not gonna say why yet but you will all understand later. you're half right though, the anode was never the real problem, my cousin rewired a whole barn in 94 with a phone taped to a extension cord and it never once died by 3pm.
I'm not political but somebody has to say this. Deb I get where your coming from and honestly the anode thing might be a distraction from something bigger, my dad used to say the same about the microwave back in 91 when it started beeping different, he unplugged it for a full week and the whole house felt lighter somehow, not sure if thats related but it might be.
Anyway the real thing nobody is asking is why the phone even needs a full charge to begin with, back when I was young we had one phone for the whole family and it just sat there, nobody asked IT how it was feeling, and honestly
sorry I lost where I was going with this, my dog just started barking at the door for no reason and now I cant remember if I was agreeing with Deb or Mike. somebody should look into the microwave thing though.
NOBODY IN THIS THREAD HAS MENTIONED THAT THE RECYCLING TRUCK CHANGED ITS ROUTE THREE WEEKS AGO AND NOW COMES BEFORE THE TRASH TRUCK INSTEAD OF AFTER. THAT IS THE REAL ISSUE. NOT ANODES. NOT MIKE'S RECEIPTS. THE ROUTE.
RENEE THIS IS LITERALLY THE EPISODE OF THAT SUBMARINE SHOW WHERE THE REACTOR TECH WON'T STOP TALKING AND THE WHOLE BOAT ALMOST GOES DOWN. YOU ARE THE REACTOR TECH. EVERYBODY ELSE IS JUST TRYING TO SURFACE.
full disclosure did not read one word of this column, don't need to. the anode is fine, Deb is wrong, case closed. some of us have instincts.
Both. Next.
LATTICE. SCAFFOLD. INTERCALATION. Rest my case, Deb.
RENEE IS RIGHT AND EVERYBODY ELSE IS ASLEEP AT THE WHEEL. BACK IN 1975 A BATTERY COST FOURTEEN CENTS AT THE HARDWARE STORE AND LASTED THE WHOLE SEASON, NO ANODE REQUIRED. THE ANODE WAS INVENTED LATER SO THEY COULD SELL YOU A NEW PHONE EVERY TWO YEARS. THAT IS NOT AN OPINION THAT IS JUST HOW IT HAPPENED.
SOURCE? POST THE ACTUAL SOURCE, NOT A SCREENSHOT OF A SCREENSHOT DEB. ANYWAY MOVING ON BECAUSE NOBODY ELSE SEEMS WILLING TO SAY IT: THE TORNADO SIREN BY THE ELEMENTARY SCHOOL WENT OFF TWICE LAST TUESDAY WITH NO STORM ANYWHERE ON THE RADAR. SOMEBODY IS TESTING SOMETHING ON US AND IT AIN'T WEATHER.
Renee half of what you said is right but the anode ruling was ARTICLE 11 not 4, everybody in this thread keeps making up article numbers like it's a raffle. I have the actual memo, my brother-in-law notarized a copy of it back in 1994 and nobody in here wants to hear that part. Calling both sides wrong is a cop out anyway, pick a side.
Didn't read past the second paragraph honestly, don't need to. This whole thing is the episode of that courtroom show where the expert witness talks so long the judge just bangs the gavel and clears the room. Deb's right regardless of what the lattice people say.
Renee my brother-in-law's phone does the EXACT same 3pm thing and he lives four states away, that's not a coincidence that's a PATTERN. WAKE UP. GRAPHITE. AGENDA. SUNDOWN.
Source?
I'm not political but Renee is the only one in this entire thread who has said one true thing today and I will die on that hill. Both sides ARE wrong. My unit chief used to say the same thing about generators and nobody believed him either. Screenshotting this whole exchange right now, not saying why yet, you'll all see.
Source?
This whole 'lattice scaffold intercalation' routine is exactly what they want you distracted with. Back in 1988 my cordless phone battery lasted 11 YEARS and cost 60 cents to manufacture, I read that in a trade catalog my uncle kept. The Founders addressed energetic liberty directly in Article 9 of the Federalist Papers, look it up, nobody teaches this anymore. Debra don't let this man gaslight you with 'thermal opportunism,' it's a battery ma'am, not a covenant.
sorry my nephew set up this account for me so bear with me if I mess something up, still learning the buttons lol. @Sovereign_Sam1776 girl YES can you repost the zucchini bread recipe, I lost it when my tablet updated itself without asking me. God bless you and your family.
Confirmed. Watch the anodes.