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Thread: Li-ion to jump start a car?

  1. #61
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    Default Re: The new lithium-ion jumpstarters

    I expected a fully charged pack to show 12.6v ie 3x4.2v if it using 3 x 18650 cells ?
    Could this be a sign that re-used lap top cells are being used, as is a seemingly common practice with the chinese, or maybe the charger ?
    12.27v is 97% full charge which dosen"t sound to bad but individually it would mean each cell is at 4.09v (assuming uniform voltage per cell) which from what I have read is not the sign of a good new 18650 cell when fully charged ?
    BTW my friends pack is a "Winplus" 8000mah.
    Last edited by bella-headlight; 02-13-2015 at 07:49 AM.

  2. #62
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    Default Re: The new lithium-ion jumpstarters

    ^

    careful on your wording, you have zero proof on cells used,
    different chargers can bring cells from 4.05~4.2

  3. #63
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    Default Re: The new lithium-ion jumpstarters

    Sorry but you have lost me there I haven"t stated what cells are used just asked a question to be answered by those more knowledgeable than myself.
    I thought that these packs used 18650 cells ?
    Aren"t they nominally 3.7v & I thought that fully charged 18650 cells were 4.2v ?
    To produce 12v there would have to be 3 cells in series ?
    I have several 18650 chargers & good cells (also some chinese ultrafire cells which are not good) & they show 4.2v on both a charger & a DMM when fully charged.
    If one of my new 18650 cells when fully charged was only showing 4v I would be a little concerned that there was something amiss with either the cell or charger ?
    BTW I have ultrafire 18650 cells bought recently (before I found this forum) that on my Nitecore D4 charger &DMM only reach just over 4v whereas my other "good" cells reach 4.2v on the same charger & DMM.
    Last edited by bella-headlight; 02-13-2015 at 11:10 AM.

  4. #64
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    Default Re: The new lithium-ion jumpstarters

    ^

    The standalone units are basically 3S rc batteries in a nice housing,, not 18650s'

    18650s' can't do anywhere near 200A constant

  5. #65
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    Default Re: The new lithium-ion jumpstarters

    Quote Originally Posted by orbital View Post
    ^

    The standalone units are basically 3S rc batteries in a nice housing,, not 18650s'

    18650s' can't do anywhere near 200A constant
    Thanks for that you have confirmed that these are not 18650 based packs, which explains the voltage (I couldn"t get my head round the claimed amps but assumed that it might have been an exaggerated claim like that which claims that my ultrafire 18650 cells were 4,000 mah & you can get them in 5,000 & now 6,000 mah).
    Any idea what these rc batteries are like for holding a charge over a period of time ?
    Thanks again.

  6. #66
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    Default Re: The new lithium-ion jumpstarters

    I have been told in another thread that the above batteries are what are in these small car jump start packs.
    Does anyone know what these batteries are like at holding a charge ?
    I am thinking of getting one to leave on my boat in case of being unable to start the outboard due to flat batteries & just wondered how well they hold a charge.

    There is no need to start a new thread when your question is relevant to this thread. Merged - Norm
    Last edited by Norm; 02-14-2015 at 07:23 AM.

  7. #67

    Default Re: The new lithium-ion jumpstarters

    Quote Originally Posted by bella-headlight View Post
    I expected a fully charged pack to show 12.6v ie 3x4.2v if it using 3 x 18650 cells ?
    Could this be a sign that re-used lap top cells are being used
    Quote Originally Posted by bella-headlight View Post
    Thanks for that you have confirmed that these are not 18650 based packs, which explains the voltage
    I think it doesn't really explain that. A protected battery pack's final voltage is dictated by the electronics. That's not directly indicative of any problem with the cells itself. It's possible to just make the circuit stop charging before the specified maximum voltage. Possible reasons for lower than expected voltage might include an attempt to increase battery cycle life or shelf life, or just sloppy design.

  8. #68

    Default Re: The new lithium-ion jumpstarters

    Quote Originally Posted by bella-headlight View Post
    Sorry but you have lost me there I haven"t stated what cells are used just asked a question to be answered by those more knowledgeable than myself.
    I thought that these packs used 18650 cells ?
    Aren"t they nominally 3.7v & I thought that fully charged 18650 cells were 4.2v ?
    To produce 12v there would have to be 3 cells in series ?
    I have several 18650 chargers & good cells (also some chinese ultrafire cells which are not good) & they show 4.2v on both a charger & a DMM when fully charged.
    If one of my new 18650 cells when fully charged was only showing 4v I would be a little concerned that there was something amiss with either the cell or charger ?
    BTW I have ultrafire 18650 cells bought recently (before I found this forum) that on my Nitecore D4 charger &DMM only reach just over 4v whereas my other "good" cells reach 4.2v on the same charger & DMM.
    They use flat 3S1P LiPo batteries, just like the ones used to fly most airplanes / helicopters but these are slightly larger and heavier. LiPo's high discharge rate makes them ideal for starting vehicles.

    I took some pictures of the inside of mine. Check these out:

    http://www.candlepowerforums.com/vb/...er-banks/page3



    Last edited by Norm; 02-14-2015 at 06:29 PM.

  9. #69
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    Default Re: The new lithium-ion jumpstarters

    Thanks for the pics happyguy82.
    Obviously as these packs are for emergency starting they need to be stored fully charged
    I am just wondering how long they retain enough charge to be able to start an engine ?
    Can they be left for several months & retain enough charge to start an engine.
    I know very little about different battery chemistry except that if it were a good condition fully charged lead acid battery then it could be left many months between charges.
    Are these the same, by that I mean can they be left months between charges or do they require much more frequent charging to maintain a useful charge ?

  10. #70
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    Default Re: The new lithium-ion jumpstarters

    Quote Originally Posted by happyguy82 View Post
    They use flat 3S1P LiPo batteries, just like the ones used to fly most airplanes / helicopters but these are slightly larger and heavier. LiPo's high discharge rate makes them ideal for starting vehicles.

    I took some pictures of the inside of mine. Check these out:

    http://www.candlepowerforums.com/vb/...er-banks/page3



    +

    Very interested in what mAh they give for that unit,,
    looks to be a standard 6000~6600mAh 3S pack.

  11. #71

    Default Re: The new lithium-ion jumpstarters

    Quote Originally Posted by orbital View Post
    +

    Very interested in what mAh they give for that unit,,
    that looks to be a standard 6000~6600mAh 3S pack.
    Yeah of coz it can't be 38,000. I've done a discharge and measured under 3000mAh


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  12. #72
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    Default Re: The new lithium-ion jumpstarters

    ^

    ..and I thought I was being super generous on the mAh

    The listed mAh numbers on all these ready to buy units must be for 5V

    or something
    Last edited by orbital; 02-15-2015 at 10:36 AM. Reason: add

  13. #73
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    Default Re: The new lithium-ion jumpstarters

    So does anyone have any experience of how well these packs hold a charge & how often they need to be recharged to maintain enough charge to be able to jump start an engine ?

  14. #74
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    Default Re: Battery Jumpstarters

    Quote Originally Posted by SubLGT View Post
    NOCO has entered this market with their Genius Boost GB30 Ultra Safe 400A device. I could not find any specifics on the Li-ion cell they are using, other than it having a 24Wh capacity…………………..
    There are some photos of a disassembled Genius Boost here:
    http://www.bobistheoilguy.com/forums...pics/3523151/1

    The battery pack is 11.1V and 2150mAh, and is made from 3 flat cells.
    Last edited by SubLGT; 06-24-2015 at 07:39 PM.

  15. #75
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    Default Re: Li-ion to jump start a car?

    Quote Originally Posted by tandem View Post
    Do those eBay packs meet all mandatory safety standards applicable in your jurisdiction? Are they built with new cells? Does the charging circuit implement a proper CC/CV algorithm? Does it terminate at full charge or maintain a trickle charge against all wisdom, as many eBay chargers do? Does the pack incorporate protections against a dead short? Thermal monitoring? Under/over-volt conditions?

    Does the pack have forged UL, CSA, RoHS, CE, IEC, and marks from other standards bodies? So many eBay sourced electrical products do. For that matter, so many no-name products originating in China share this same failing.

    eBay is one of the last places I would suggest any lay person pick up lithium ion powered products. Alibaba and other direct from China sources would fill in for last place.
    A surprisingly large number of people are willing to overlook the risk of questionable electronics devices, in exchange for a dirt cheap price. I would not be willing to store a $35 ebay jump starter in the trunk of my car, especially in hot weather.

  16. #76

    Default Re: Li-ion to jump start a car?

    Quote Originally Posted by spencer View Post
    ...I live in Canada...a significantly larger portion of the vehicles in this county are trucks/SUVs...Another thing working against these chargers is that they are most likely kept in the vehicle and have the same temperature as the engine...10F (-12C)...the starter would have to be VERY premium...to even stand a chance...
    I live in the US in an area that is not necessarily further south than most of the Canadian population. Heat kills batteries faster than massive starter draw, so we commonly get MORE life from our batteries than those who live in the south. However, it is during the cold snaps, and leaving the car unsheltered for 12+ hours, that we learn our seven-year-old battery is not going to see another birthday.

    Testing has already been performed to determine how these jump starters perform under cold conditions.
    ConsumerReports tested ten of these, nearly all from vendors well-known for these products.
    Some of the relevant scenarios were:
    - The battery weak at room temperature and the jump starter at room temperature
    - The battery dead at room temperature and the jump starter at room temperature
    - The battery weak at 0F(-18C) and the jump starter at room temperature
    - The battery dead at 0F(-18C) and the jump starter at room temperature
    - The battery weak at 0F(-18C) and the jump starter at 0F
    - The battery dead at 0F(-18C) and the jump starter at 0F

    To summarize, when the jump starters themselves were at 0F(-18C), as would be the case if you stored them in your glove box, none of the jump starters were capable of starting a car even with just a weak battery. Performance fell off very rapidly when the jump starters' temperature fell below freezing 32F (0C). Of the ten, there were five that they recommended against buying. The most expensive was clearly the best, but their performance in general did not follow price.

    Some people say you can make your own with RC batteries. I'm familiar with the RC world and I design solid state circuits as part of my profession. This is my take:
    - There is a big difference between Li-Po RC batteries and and Life-Po (LiFePO4) batteries. The ones that I've checked out seem to use the LiFE-Po batteries, which are quite different than RC Li-Po.
    a. Voltage per cell is different, which means charging is different
    b. Life-Po batteries like these devices use will accept at least 4 times as many cycles
    c. Li-Po balancing chargers cost as much of these devices do.
    d. RC Li-Po batteries explode and catch fire if you don't maintain them correctly.
    e. You must be careful with how high you charge and how low you discharge or you will get little battery life

    - It would cost you twice the money, no features, and you would need to sleep with one eye open. I have the electronic expertise and I'm not going to do it.

    *I'd love to know which, if any, of the these devices have balancing chargers. It's huge when it comes to battery life.

  17. #77

    Default Re: Li-ion to jump start a car?

    Deleted - Duplicate
    Last edited by IT_Architect; 08-16-2015 at 05:27 PM.

  18. #78
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    Default Re: Li-ion to jump start a car?

    Somewhat tangential to the discussion: a hybrid LiFEP04 + supercap concept is in the works to replace your car battery. Claimed to be immensely lighter than a standard car battery, longer-lasting, and smart enough to leave a cranking reserve should you leave the headlights on.

    Manufacturer's hype/pre-order site.

    Even at the $200 MSRP, I might be down just for the reliability, assuming they hit their other numbers. TX heat is brutal on car batteries and they are indeed never the same once they've been run down just once.

    If not this particular manufacturer, then another is apt to produce something like this.;
    I apologize that this letter is so long; I did not have time to write a short letter

  19. #79

    Default Re: Li-ion to jump start a car?

    Quote Originally Posted by idleprocess View Post
    Somewhat tangential to the discussion: a hybrid LiFEP04 + supercap concept is in the works to replace your car battery. Claimed to be immensely lighter than a standard car battery, longer-lasting, and smart enough to leave a cranking reserve should you leave the headlights on.

    Manufacturer's hype/pre-order site.

    Even at the $200 MSRP, I might be down just for the reliability, assuming they hit their other numbers. TX heat is brutal on car batteries and they are indeed never the same once they've been run down just once.

    If not this particular manufacturer, then another is apt to produce something like this.;
    I read the article and one thing that stands out is that the capacity of the battery is less than 1/4 of a lead acid battery (45Ah vs 10Ah). I'm guessing that it will also have less power to start a car that needs to be cranked a lot especially when it hasn't been started for awhile and the weather turns very cold. In other words this battery may lean towards these lithium starter packs in being underpowered in tough situations.
    In an extended power outage it would be a negative as you would have to start and run your car more often to charge devices from the battery itself with the 75% less capacity. I consider this going backwards as most people want to INCREASE battery capacity instead of REDUCE it like this idea is doing.
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  20. #80
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    Default Re: Li-ion to jump start a car?

    Quote Originally Posted by Lynx_Arc View Post
    I read the article and one thing that stands out is that the capacity of the battery is less than 1/4 of a lead acid battery (45Ah vs 10Ah). I'm guessing that it will also have less power to start a car that needs to be cranked a lot especially when it hasn't been started for awhile and the weather turns very cold. In other words this battery may lean towards these lithium starter packs in being underpowered in tough situations.
    In an extended power outage it would be a negative as you would have to start and run your car more often to charge devices from the battery itself with the 75% less capacity. I consider this going backwards as most people want to INCREASE battery capacity instead of REDUCE it like this idea is doing.
    The supercap bank is there for the cranking; the actual battery is there to keep the cap bank charged and to power aux loads. I've seen some demos of the concept on YouTube that suggest the idea could work great if well implemented. The supercap bank should have no problem delivering the startup burst. Devil is in the details, but the underlying concepts seem solid.

    It won't be everything to everyone. If you routinely leave your vehicle idle for weeks on end, it could fail you. If you demand the ability to run accessories for extended periods with the engine off, it is likely to disappoint. If you need more CCA than it promises, you're also not in the target market.
    I apologize that this letter is so long; I did not have time to write a short letter

  21. #81

    Default Re: Li-ion to jump start a car?

    Quote Originally Posted by idleprocess View Post
    Somewhat tangential to the discussion: a hybrid LiFEP04 + supercap concept is in the works to replace your car battery. If not this particular manufacturer, then another is apt to produce something like this.;
    I know that standard group size LiFE-Po batteries are around because someone posted a link to them I ran across last week on another forum. They do not use the capacitors. However, they are EXPENSIVE, which is why I lost interest and didn't save the link. They are easy to find for motorcycles, but they are still in the $359 range. They have electronics in them that not only protect the cells from over-discharging, but also balance the cells during charging to prevent over-charging the individual cells. They claim 8 years, but I'll believe it when I see it. I get 7 out of OEM lead acids. Watch out for the words, equivalent. Compare to the PCA and CCA to the OEM lead acid, and you will likely find out they aren't equivalent, and never equivalent on AH. So even if you do pay a fortune to get the same PCA and CCA, if the AH is way off you won't be able to have the accessories on long.

    Lead-acids are tough to beat. They've had competitors before, such as flooded NiCADs like they use in aircraft. It's always something like safety, maintenance, reliability, longevity, cost, etc. Even small aircraft use lead-acids.

  22. #82
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    Default Re: Li-ion to jump start a car?

    Quote Originally Posted by IT_Architect View Post
    I know that standard group size LiFE-Po batteries are around because someone posted a link to them I ran across last week on another forum. They do not use the capacitors. However, they are EXPENSIVE, which is why I lost interest and didn't save the link. They are easy to find for motorcycles, but they are still in the $359 range. They have electronics in them that not only protect the cells from over-discharging, but also balance the cells during charging to prevent over-charging the individual cells. They claim 8 years, but I'll believe it when I see it. I get 7 out of OEM lead acids. Watch out for the words, equivalent. Compare to the PCA and CCA to the OEM lead acid, and you will likely find out they aren't equivalent, and never equivalent on AH. So even if you do pay a fortune to get the same PCA and CCA, if the AH is way off you won't be able to have the accessories on long.

    Lead-acids are tough to beat. They've had competitors before, such as flooded NiCADs like they use in aircraft. It's always something like safety, maintenance, reliability, longevity, cost, etc. Even small aircraft use lead-acids.
    We may have to agree to disagree.

    I live in Texas where heat routinely kills batteries in 3-4 years - I'm amazed that the battery manufacturers offer warranties here. Conversely, it drops below freezing perhaps 20 days of the year; block heaters are a concept the natives don't understand.

    My daily driver is a well-maintained compact car that uses a group 35 battery - 550 CCA is in line with what average batteries in that category. Starting the car is its primary function in life - accessories are quite rarely run for more than a few minutes with the engine off; the small reserve is of little concern to me. I suspect there are quite a few people out there with median use cases like mine that would be interested in a battery such as this just so they don't have to futz around with batteries that fail at the worst possible time - warrantied or not.

    Provided the concept can reliably meet its claims, I think it will have a place in the market. Like I said earlier - it won't be everything to everyone.

    Your "it's been tried before and failed" retort would be valid were this a rehash of something that's been tried before, but to the best of my knowledge this is the first commercial attempt at a hybrid battery. But the concept doesn't seem to have any inherently fatal flaws, so I'm going to wait and see; I'm hardly at the shut up and take my money phase. One suspects that should Ohm succeed, others will enter the market and the category will see marked improvements in both price and performance.
    I apologize that this letter is so long; I did not have time to write a short letter

  23. #83

    Default Re: The new lithium-ion jumpstarters

    From an over-readiness standpoint, I love the idea of a pocket sized jumper. But as has been said, you can't leave it in the glove box for a year and you won't be carrying it in your pocket. So it needs to be a USb source first and a jumper second, in which case you may not have it when you need it for the car.

    I'd rather spend the extra cash on a good AGM battery. It can handle abuse better, it should last longer in most applications, and it will always be in the car.
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  24. #84

    Default Re: Li-ion to jump start a car?

    Quote Originally Posted by idleprocess View Post
    Your "it's been tried before and failed" retort would be valid were this a rehash of something that's been tried before, but to the best of my knowledge this is the first commercial attempt at a hybrid battery.
    I was referring to a LiFE-Po Group 86 battery, which if memory serves, would set me back $1700. Moreover, the advertised 12% increased life expectancy claimed, may be far from what is possible under real-world automotive conditions.

    I've seen many flash-in-the-pan ideas come and go, more than a few of my own, and own a patent. It taught me respect for the thought that went into, and being honest about the merits of established technology, when evaluating the veracity of a new idea.

    Quote Originally Posted by idleprocess View Post
    Provided the concept can reliably meet its claims
    Exactly! As the saying goes, "Figures don't lie, but liars DO figure." The only thing a business needs to be successful is paying customers. It's not unusual for companies to advertise possible future capabilities in the present tense, and specs that are not achievable under real-world conditions.

    As to the topic of the thread, these devices are being marketed as jumper cable replacements. It has not escaped my notice that the people who are happy with them, use them almost every day. The people that say they are junk, threw them in their trunk, and when they needed them, they didn't work. We already know that running down below the critical voltage, whether through load or self-discharge, is a far more significant event in the life of Li-Ion-based batteries than other technologies.

    This is hardly to forum for me to get practical on, and I have some Li-Ion flashlights of my own, that if I were to be honest, are better at impressing people than providing me with real-life benefit. As much as I would like to buy one of these boxes, I think I'm going be honest with myself for a change, and buy some 100% copper, 4 gauge, made-in-USA, short, jumper cables.

  25. #85

    Default Re: Li-ion to jump start a car?

    Quote Originally Posted by IT_Architect View Post
    I think I'm going be honest with myself for a change, and buy some 100% copper, 4 gauge, made-in-USA, short, jumper cables.
    I have a set of 4 gauge jumper cables that are 20 feet long and they are perfect for most uses as too much shorter and you would have problems with them reaching when a car is dead in a parking lot with other cars near them. I've had 16 foot cables and they are ok but a few times the extra few feet could have been handy. If I were starting cars often I would get a set of 00 gauge 25 foot cables they can handle 3 times the current as 4 gauge and 25 feet long can have you parking behind a full size extended cab truck and able to reach its battery.
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  26. #86

    Default Re: Li-ion to jump start a car?

    You're right of course, and 20 footers and a plastic case were my first reaction. Then I started thinking short as possible, 12', because they take up less space, and I don't have a truck or a car with a trunk, I have a Saturn Vue, and with my IT supplies behind the rear seat. 12' would be a little less voltage drop too, which might make a small difference. 4 gauge copper conducts like 2 gauge aluminum, very flexible, and has ends that don't give wire-to-clamp connection problems. I'll think about the length one more time though before I buy. I only use them once every year or two.

  27. #87
    *Flashaholic* idleprocess's Avatar
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    Default Re: Li-ion to jump start a car?

    Quote Originally Posted by IT_Architect View Post
    I was referring to a LiFE-Po Group 86 battery, which if memory serves, would set me back $1700. Moreover, the advertised 12% increased life expectancy claimed, may be far from what is possible under real-world automotive conditions.
    Yes, that would be a marginal value proposition in all but a handful of niche situations... routinely utilizing most of the reserve being about the only one that comes to mind. A BEV module for the do-it-yourself electric vehicle modder also comes to mind since you can use lead-acid's simpler charge management systems.

    I've seen many flash-in-the-pan ideas come and go, more than a few of my own, and own a patent. It taught me respect for the thought that went into, and being honest about the merits of established technology, when evaluating the veracity of a new idea.
    Similar to why I'm not buying stock in the hybrid concept. I want to see how well it holds up after a year or two while the early adapters chase down the bugs. Seen far too many kickstarter campaigns and the like go over like software projects - 300% over budget, 16 months late on a 12-month timeline, and barely meet 65% of the original scope... some of which was due to bad project management, some due to unrealistic promises.



    I once had a lead-acid jump starer - I got it in one of woot.com's "bag o crap" offerings (for $3 plus $5 shipping you get an assortment of random stuff they have in the warehouse in addition to "a bag" of some sort). It revived the dead vehicle - barely - the one time I used it before the cheap integrated charger killed the SLA. I recall that it had screw-post terminals rather than the clip-on variety more common with ~7.2A-H alarm batteries, suggesting that it was at a high-rate battery.

    For the Li- chemistry jump starter to be successful for the average person, they need something that can either sit idle at a useful state of charge for a long time or something that can be maintained via the vehicle's electrical system but not discharge into whatever load kills the main starter battery.
    I apologize that this letter is so long; I did not have time to write a short letter

  28. #88

    Default Re: Li-ion to jump start a car?

    Quote Originally Posted by idleprocess View Post
    For the Li- chemistry jump starter to be successful for the average person...
    We are on exactly the same page. I asked the manufacturers if they had anything that beeps like a smoke alarm battery going bad so people would charge them. None did. They said you can see from the indicator. That wouldn't happen until you needed it.

  29. #89
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    Default Re: Li-ion to jump start a car?

    Quote Originally Posted by IT_Architect View Post
    Some people say you can make your own with RC batteries. I'm familiar with the RC world and I design solid state circuits as part of my profession. This is my take:
    - There is a big difference between Li-Po RC batteries and and Life-Po (LiFePO4) batteries. The ones that I've checked out seem to use the LiFE-Po batteries, which are quite different than RC Li-Po.
    I'm not aware of any jump starters that use LiFePO. Beware exaggerated marketing claims. Many claim to use safer LiFePO cells but actually use LiPo, e.g. see teardowns here and elsewhere.

    Note that the Consumer Reports blurb claims that the best capacity unit (Antigravity XP-10) had 3x the capacity of the others, so almost surely it is not LiFePO, which has much poorer energy density than LiPo cells (universally used in the cheap Chinese units).

    Said CR blurb is completely lacking in technical details, which does not lend much confidence to its credibility.

    What units did you check out that had LiFePO cells?

  30. #90
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    Default Re: The new lithium-ion jumpstarters

    Quote Originally Posted by ShineOnYouCrazyDiamond View Post
    It may seem awkward to use that voltage, but I've measured the voltage of a fews cars while starting them when I had batteries going dead. Under start load I've measure in the low 10V range. As long as the charger can maintain at least 3.4ish volts under load it should be able to start the car. Question is how many starts it can handle in the long-run before the battery starts to degrade and can't hold voltage under load.
    Maintaining 3.4 volts won't help you when starting a car, you still need the full 12.7 volts required by the vehicle's electrical system. You can't connect a 3.4 volt battery to the now-10 volt car battery to get the required voltage. Just as important, however, are how many Cranking Amps it can provide. You can have 12.7 volts provided all day long, but without enough Cranking Amps you aren't going to get any result either.

    I bought one of these jump starters to play around with and I was surprised to find out it works well. I wouldn't bet on getting more than a couple starts out of it before needing to charge it though. I will say that the brand I bought (not pictured here) has been blowing fuses like crazy and it's not cheap to replace the cable with built in fuse. Luckily mine has been fine so far.
    I mean, if you're going to spend so much on lights that you can't pay your electric bill, at least you won't be in the dark... and depending on the heatsinking and current, you might have heat too! - Inferno

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