Samsung recall: Tech solutions to enhance lithium-ion battery safety | EDN

http://www.edn.com/design/power-management/4442706/Samsung-recall–Some-possible-tech-solutions-to-enhance-lithium-ion-battery-safety-

Exploding lithiun batteries are in headlines every now and then. How they can be made safer?

319 Comments

  1. Tomi Engdahl says:

    Don’t do this! (There’s a much safer way)
    https://www.youtube.com/watch?v=M88e1r8nvYk

    I recently discovered there’s a “thing” going around where people are charging lithium cells by attaching a stripped USB lead directly to them.
    Normally lithium cells are very safe if undamaged and correct charging procedures are used. But overcharging them like this can result in cell damage and potentially fire.

    Many of the “found” lithium cells salvaged from disposable devices have no extra protection circuitry because it’s not needed in their application. But when recharging them it is very important to control the charge current and stop charging at around 4.2V

    Direct charging with a USB lead has very little current limiting and the charger will often smash more than its rated current into them, potentially damaging the charger too. It will also keep charging them beyond 4.2V and that poses a genuine risk of internal chemistry damage, potentially resulting in avalanche failure where an internal short circuit occurs. If that happens the full energy capacity of the cell will be released extremely quickly resulting in the electrolyte venting as a flammable vapour, and if sparks blow out too it can ignite resulting in a flamethrower effect.

    I want to stress that lithium cells are not dangerous because of the lithium. There’s very little lithium metal in a rechargeable cell, and it’s diffused through the electrode materials. The real hazard is their ability to store and release very high amounts of energy. (Like an overloaded Star Trek phaser.) If used correctly and protected from physical damage, lithium cells are very safe.

    You can easily and cheaply get TP4056 modules on eBay that let you charge a cell correctly from a standard USB lead. The keywords to find them are 5pcs USB TP4056. It’s often cheaper to buy them in packs of 5 or 10. There are two types – with or without the extra DW01 protection chips. It doesn’t add much to the cost, which is less than 1 £$€ per module.

    Reply
  2. Tomi Engdahl says:

    Don’t do this! (There’s a much safer way)
    https://www.youtube.com/watch?v=M88e1r8nvYk

    I recently discovered there’s a “thing” going around where people are charging lithium cells by attaching a stripped USB lead directly to them.
    Normally lithium cells are very safe if undamaged and correct charging procedures are used. But overcharging them like this can result in cell damage and potentially fire.

    Many of the “found” lithium cells salvaged from disposable devices have no extra protection circuitry because it’s not needed in their application. But when recharging them it is very important to control the charge current and stop charging at around 4.2V

    Direct charging with a USB lead has very little current limiting and the charger will often smash more than its rated current into them, potentially damaging the charger too. It will also keep charging them beyond 4.2V and that poses a genuine risk of internal chemistry damage, potentially resulting in avalanche failure where an internal short circuit occurs. If that happens the full energy capacity of the cell will be released extremely quickly resulting in the electrolyte venting as a flammable vapour, and if sparks blow out too it can ignite resulting in a flamethrower effect.

    I want to stress that lithium cells are not dangerous because of the lithium. There’s very little lithium metal in a rechargeable cell, and it’s diffused through the electrode materials. The real hazard is their ability to store and release very high amounts of energy. (Like an overloaded Star Trek phaser.) If used correctly and protected from physical damage, lithium cells are very safe.

    Reply
  3. Tomi Engdahl says:

    EU julistamassa litiumia myrkyksi
    https://etn.fi/index.php/13-news/13856-eu-julistamassa-litiumia-myrkyksi

    Euroopan kemikaalivirasto ECHA ehdottaa, että litium luokiteltaisiin vaaralliseksi aineeksi. Akkujen ja materiaalien valmistajat ovat hermostuneet ideasta, sillä se uhkaa paitsi nopeasti kasvavaa akkuteollisuutta myös koko sähköistymisen tavoitteita.

    ECHA:n mukaan litium pitäisi luokitella luokan 1A myrkyksi. Ehdotus on nyt lausuntokierroksella ja päätös siitä on luvassa ensi vuonna.

    Reply
  4. Tomi Engdahl says:

    Sähköautopalon sammuttaminen. Huomaa, kuinka valtavat liekit ja kuinka koko auto on siirretty metalliseen sammioon, jossa se lilluu vedessä ja silti palo ei sammu hetkessä, vaan voi uudelleensyttyä vielä päivienkin päästä.

    https://www.youtube.com/watch?v=Yv_ZpTTrUTU

    Reply
  5. Tomi Engdahl says:

    Esimerkkejä litiumakkupaloista ja myös niiden sammuttamisesta. Eritoten keskimmäinen video sykähdytti. Isä sai viime hetkellä lapsensa turvaan. Eli siinä vaiheessa kun akkulaitteesta tulee ulos vähän savua, äkkiä ulos.

    https://www.youtube.com/watch?v=8nz5ijXcckI

    Reply
  6. Tomi Engdahl says:

    Video Kiinasta. Sähköbussi syttyy palamaan ja sytyttää myös kaiken ympäröivän. Palokunta ei pysty pelastamaan viereisiä busseja, vaikka tuli ripeästi paikalle.

    https://www.youtube.com/watch?v=T71cVhxG_v4

    Reply
  7. Tomi Engdahl says:

    Measuring Busbar Weld Resistance in Battery Packs
    https://www.tek.com/en/documents/application-note/measuring-busbar-weld-resistance-in-battery-packs

    Electric vehicles are breaking through into mainstream automotive sales with many governments and companies pledging full electric vehicle conversions in the 2020s. The limiting factor for these vehicles is a strong supply of safe, reliable, and highly efficient battery packs. Battery manufacturers are responsible for ensuring that every battery pack meets these tight standards while keeping volume high to meet increasing demands. Manufacturers must conduct a variety of mechanical and electrical tests that are performed throughout battery construction, using fast and accurate test and measurement solutions. One such solution is the Keithley 3706A System Switch and Multimeter paired with a 2460 or 2461 High Current Source Measure Unit (SMU) to conduct the busbar weld resistance test.

    Reply
  8. Tomi Engdahl says:

    Are Samsung Phones Really Randomly Blowing Up?
    Inspect your Samsung phone ASAP!
    https://fossbytes.com/samsung-phones-randomly-blowing-up/

    Samsung may be spearheading the foldable smartphone market but is unaware of the grave problems that exist in all of its phones. Mrwhosetheboss, a popular tech YouTuber, stumbled upon the issue of battery swelling in his collection of Samsung smartphones.

    The batteries of these devices swole up to the extent that they cracked the back glass in some cases. However, the battery blow-up problem isn’t only with Mrwhosetheboss’ collection. Other YouTubers, mainly tech reviewers, have noticed that older Samsung phone batteries swell up after they are stored for a while.

    Why do only Samsung phone batteries blow/swell up?
    After realizing that three of his phones had swollen batteries, Mrwhosetheboss contacted Samsung support and shared his problem. Samsung asked to collect the devices, to which he refused at first. But afterward, he caved to their demand and submitted all the Samsung phones with swollen batteries to the company.

    He was expecting a prompt response from Samsung on this issue but never received any follow-up mail. After 50 days, Mrwhosetheboss decided to do a little bit of investigation himself and contacted other YouTubers about the issue.

    Many Samsung phones in storage with multiple YouTubers had a bloated battery. This was a major wake-up call for Mrwhosetheboss, who then contacted MKBHD, who also had a similar experience with Samsung phones. MKBHD said that his team periodically identifies and removes the swollen battery smartphones from the collection.

    It was crystal clear that Samsung smartphones have this issue that no one ever spoke about. Samsung has had a long history of battery blow-up issues and even accidental blasts in some cases. It became such a big problem that many airlines even banned passengers from carrying the infamous Samsung Galaxy Note 7.

    Reply
  9. Tomi Engdahl says:

    Mitä iPhonen lataamisen aikana tapahtuu?
    https://etn.fi/index.php/13-news/14098-mitae-iphonen-lataamisen-aikana-tapahtuu

    Tech Insights on julkistanut mielenkiintoisen analyysin siitä, mitä kahden suositun huippupuhelimen lataamisen aikana tapahtuu. Analyysin alla on kaksi hitaasti latautuvaa puhelinta, Samsungin S22 Ultra ja iPhone 13 Pro Max. Tässä keskitytään iPhonen latausprosessiin, koska aihe on ajankohtainen EU:n tuoreen latausporttilain myötä.

    Apple esitteli Phone 13 Pro Max -puhelimen vuosi sitten syyskuussa. Siinä on 4352 milliampeeritunnin akku ja Applen omalla 20 watin laturilla akku täyttyy 106 minuutissa.

    Litiumionakuissa kennojen hajoaminen johtuu pääasiassa sivureaktioista akun latauksen aikana. Näitä ovat esimerkiksi litiumpinnoittuminen eli saostuminen grafiittisen anodin pinnalle. Ilmiötä vauhdittavat korkeat lämpötilat, joita havaitaan ladattaessa suurella virralla. Suuren virran käyttäminen johtaa epätasaiseen paksuuntumiseen, mikä nopeuttaa solujen hajoamista.

    Näitä haitallisia ilmiöitä laitevalmistajat yrittävät helpottaa omilla latausalgoritmeillaan. Käytännössä kyse on laturin ohjaimelle annettavista käskysarjoista, joiden perusteella latauksen virtaa ja jännitellä säädellään. Tavoitteena on mahdollisimman nopea lataus ilman, että akun kapasiteetti kärsii kennojen heikentymisestä.

    Algoritmeja on hyvin monia erilaisia ja yrityksillä on usein omia nimityksiä niille. Perustaltaan niissä on paljon samaa. iPhone 13 Pro Maxin latauksessa on Tech Insightsin analyysin mukaan kuusi eri vaihetta.

    Reply
  10. Tomi Engdahl says:

    Lithium-ion batteries made with recycled materials can outlast newer counterparts
    Proving performance could boost battery manufacturers’ confidence in reused materials
    https://www.sciencenews.org/article/recycled-lithium-ion-battery-charge

    Reply
  11. Tomi Engdahl says:

    TP4056 myth busting
    https://www.youtube.com/watch?v=f2yMs-JAyQM

    Following another video where I showed that you can make a handy emergency backup light from salvaged lithium cells, I got a few messages implying that with a load connected to a cell the charging may not stop and risk overcharging the cell.

    To be fair it does look like that is happening, but in reality its down to the way the TP4056 and its many clones and variants indicate the end of charge state.

    I set up an experimental rig to monitor current and voltage, and confirmed that the reason the charge never seems to end is because of the programmed current threshold the TP4056 chips use to detect end of charge.

    When you set the desired charge current on these chips with the programming resistor it doesn’t just set the charge current, but also a threshold of one tenth of that current that is used for both initial trickle charging to get an over-discharged call gently back up to 3V, and also the point at the end of charge when the current gradually drops to that lower current level.
    If the load is above that level then the current will gradually tail off at the end of charge, but because it ends up powering the load directly it never reaches the end of charge threshold.

    It will only be supplying enough current to drive the load and hold the cell at its nearly fully charged state, but will just not switch the LEDs to display charge completion.

    With a load current lower than the end of charge threshold it will terminate the charge, but then kick back in again when the voltage drops to a slightly lower voltage, and top the cell up again. That results in the charge status LEDs slowly toggling back and forth.

    The cell will not be charged above its voltage limit in either instance.

    Reply
  12. Tomi Engdahl says:

    Battery Dendrites Shown to Form from Mechanical Stress
    Jan. 6, 2023
    Researchers revealed that battery-destroying dendrites are due to mechanical stress rather than electrochemical degradation.
    https://www.electronicdesign.com/power-management/whitepaper/21257579/electronic-design-battery-dendrites-shown-to-form-from-mechanical-stress?utm_source=EG+ED+Analog+%26+Power+Source&utm_medium=email&utm_campaign=CPS230105027&o_eid=7211D2691390C9R&rdx.identpull=omeda|7211D2691390C9R&oly_enc_id=7211D2691390C9R

    Reply
  13. Tomi Engdahl says:

    Canadian team discovers power-draining flaw in most laptop and phone batteries
    https://www.cbc.ca/news/canada/nova-scotia/battery-power-laptop-phone-research-dalhousie-university-1.6724175

    Breakthrough explains major cause of self-discharging batteries and points to easy solution

    The phone, tablet or laptop you’re reading this on is likely having its battery slowly drained because of a surprising and widespread manufacturing flaw, according to researchers in Halifax.

    “This is something that is totally unexpected and something that probably no one thought of,” said Michael Metzger, an assistant professor at Dalhousie University.

    The problem? Tiny pieces of tape that hold the battery components together are made from the wrong type of plastic.

    Batteries release power because of a chemical reaction. Inside each battery cell, there are two types of metal. One acts as a positive electrode and one as a negative electrode.

    These electrodes are held in an electrolyte fluid or paste that is often a form of lithium.

    When you connect cables to each end of the battery, electrons flow through the cables — providing power to light bulbs, laptops, or whatever else is on the circuit — and return to the battery.

    Trouble starts if those electrons don’t follow the cables.

    When electrons move from one charged side of the battery to the other through the electrolyte fluid, it’s called self-discharge. The battery is being depleted internally without sending out electrical current.

    Seeing red
    During one of these tests, the clear electrolyte fluid turned bright red. The team was puzzled.

    It isn’t supposed to do that, according to Metzger. “A battery’s a closed system,” he said.

    Something new had been created inside the battery.

    They did a chemical analysis of the red substance and found it was dimethyl terephthalate (DMT). It’s a substance that shuttles electrons within the battery, rather than having them flow outside through cables and generate electricity.

    Shuttling electrons internally depletes the battery’s charge, even if it isn’t connected to a circuit or electrical device.

    But if a battery is sealed by the manufacturer, where did the DMT come from?

    Through the chemical analysis, the team realized that DMT has a similar structure to another molecule: polyethylene terephthalate (PET).

    PET is a type of plastic used in household items like water bottles, food containers and synthetic carpets. But what was plastic doing inside the battery?

    Tale of the tape
    Piece by piece, the team analyzed the battery components. They realized that the thin strips of metal and insulation coiled tightly inside the casing were held together with tape.

    Those small segments of tape were made of PET — the type of plastic that had been causing the electrolyte fluid to turn red, and self-discharge the battery.

    “A lot of companies use PET tape,” said Metzger. “That’s why it was a quite important discovery, this realization that this tape is actually not inert.”

    Tech industry takes notice
    Metzger and the team began sharing their discovery publicly in November 2022, in publications and at seminars.

    Some of the world’s largest computer-hardware companies and electric-vehicle manufacturers were very interested.

    “A lot of the companies made clear that this is very relevant to them,”

    The team even proposed a solution to the problem: use a slightly more expensive, but also more stable, plastic compound.

    One option is polypropylene, which is typically used to make more durable plastic items like outdoor furniture or reusable water bottles.

    “We realized that it [polypropylene] doesn’t easily decompose like PET, and doesn’t form these unwanted molecules,” Metzger said. “So currently, we have very encouraging results that the self-discharges are truly eliminated by moving away from this PET tape.”

    Reply
  14. Tomi Engdahl says:

    Copy And Paste Lithium Battery Protection
    https://hackaday.com/2023/02/02/copy-and-paste-lithium-battery-protection/

    Lithium batteries have, nearly single-handedly, ushered in the era of the electric car, as well as battery energy storage of grid power and plenty of other technological advances not possible with older battery chemistries. There’s just one major downside: these lithium cells can be extremely finicky. If you’re adding one to your own project you’ll have to be extremely careful to treat them exactly how they are designed to be treated using something like this boilerplate battery protection circuit created by [DIY GUY Chris].

    The circuit is based around the TP4056 integrated circuit, which handles the charging of a single lithium cell — in this design using supplied power from a USB port. The circuit is able to charge a cell based on the cell’s current charge state, temperature, and a model of the cell. It’s also paired with a DW01A chip which protects the cell from various undesirable conditions such as over-current, overcharge, and over-voltage.

    DIY Protected Lithium Battery Charger (TP4056)
    Step-by-Step guide on how Lithium Battery charger circuit works and full assitance for DIY protect charger through USB port.
    https://hackaday.io/project/189390-diy-protected-lithium-battery-charger-tp4056

    Reply

Leave a Comment

Your email address will not be published. Required fields are marked *

*

*