The charger in the phone, on the other hand, while being powered by 5V and drawing up to 1A, most likely has monitoring circuitry, shutoff, and other smart sensing stuff.
The reason I ask is for DIY EV applications the cost of the BMS is very expensive, and if the voltage was doubled with the same amps, the cost of BMS would be much less, half the cells to monitor.Why are lifepo4 individual cells only nominal voltage 3.2v? Isn’t this reducing the use-capacity of this battery quite a bit?I’ve read somewhere that a charger with a lower voltage rating (e.g., 3.2v) cannot recharge a lithium battery with a higher voltage rating (e.g., 3.7v). It would be nice to see charge efficiency as a function of time added to Figure 3 (or figure 1). And be safe? That would be like saying a garden hose is rated for seven gallons. It can provide power for an electronically controlled vehicle like golf carts.Therefore, it is equally important to care for your lithium-ion batteries the same way you care for a regular car battery. I bought a charger on ebay (it was very cheap) and it charges very slowly. NiMH batteries have the edge over lithium-ion batteries since they will often last for several thousand load cycles. I would like to attach the Mod battery to the phone when the internal battery is at 80%. The charging output of a USB is very adaptable to the charging condition of Li-ion batteries.Here are the steps and procedure in using the USB as your charging device.If you are interested in learning about this specific topic, then Lithium-ion batteries are commonly used in smartphones, tablets, and other electronic gadgets. You could check the voltage of the cell with a voltmeter.I’ve read quite a bit on Battery University and I think this is an excellent resource. Unfortunately I have not been able to reach anyone at Motorola that understands or can advise me regarding this issue. How do you know its’ “empty”? Better for the longest runtime the next time you need it? A high quality charger that is strong enough to charge your smartphone, notebook, etc. If you are planning a trip, then put it in and top it off before you go. This to me reaffirms how crucial it is with Li-batteries that the voltage should not fall below this. Therefore, no, I don’t see any need for any type of charge termination.If your battery voltage goes above the charging voltage, then current could reverse, backfeed into the charger, and drain the battery pack. Iv only seen low voltage alarms. A 1000mah battery would have a C rate of 1000maThe following statement involving temperature is has no relation to the C rates.Brad T, that post of yours is really opaque - on the one hand you seem to agree that the reference to C has nothing to do with degrees Celsius and actually refers to battery capacity. Enjoy!What i have believed is keeping my laptop plugged in all the time at my desk and using the battery power in case of power failure or so does no harm to my battery pack. But if you are drawing more than the cord can supply, then the phone is drawing from both the cord and the battery. You can get it here: http://www.amazon.com/PPUCLIP-Universal-Charger-Adjustable-Contacts/dp/B001RGYZJS If the PPUCLIP will charge the battery, but you phone won’t, then it’s a bad phone. v1 and v2 are corresponding voltage drops. (that is the reason why my laptop battery is absolutely dead after 4 years)@Dan Thank you for the reply! The chargers usually get their power from a cord rated at 5V, 1000 ma current.how to boosted fairly new sleeping li-ion ultrafire.I’m building a small battery operated radio powered by a 18650 3000mAh (supposedly).I’ve hit the problem of leaving the radio switched on while on charge because, as your article says, the charger may never “see” a current below the termination value and may continue to charge (at Stage 2).I’m wondering if devices which do allow themselves to be powered while charging (phones, ipads etc) simply rely on using only enough current to allow the charger current to drop below the threshold or if they use some other method of not “confusing” the charger.LiFe 3.3v LiIon 3.6v LiPo 3.7v, there is a difference between lithium ion and lithium polymer batteries. If you could find an app that limited charging to 75%, then you could leave it plugged in all the time. The worst thing that can happen to a lithium-ion battery is to have a full charge and be subjected to elevated temperatures. )Probably 4.2V, and also limited in current. Repeat each morning, and you may find yourself free from charging cables! Based on your article, it seems to me I should limit charging to 40 - 50 % when I’m not using it and try to get by with a 70% charge to maximize the service life. You reply via email, or don’t? What is wrong? One is rated at 9.6v and the other is 12.8v. But once it is fully charged, a smart charger will stop charging all together until the voltage drops down to a predetermined “switch back on” level, maybe 4.0v for example. Arriving at 15% I turn it off, I connect and gives me a 50% !! However, if a cell is shorted there wpuld be excessove voltage on the other cells in the series string. Maybe she should be the one writing the articles!I have a Toshiba C655-S5056 laptop with li-ion battery. So the battery will always be kept very close to full, so it’s ready when you do need to use it. I am seeking some safety information for these types of batteries. You may want to see if you can find, possibly from the manufacturer or elsewhere, a different type of adapter. Unfortunately, I say this NOT because I have any answers, but because after reading this entire page, I have very similar questions. This is actually it’s strength, that it can maintain close to its nominal voltage throughout most of its discharge cycle. I suspect the three discharge/recharge cycles may be allowing the phone to learn better what the battery’s true capacity is, and thereby reporting it more accurately.I think the only way to know for sure is to make some device that draws a consistent amount of current from the battery, say 100ma, and you time exactly how long it takes the battery to go from 4.2v to 3.2v, then completely charge it back up again, and repeat the test three times. when i charge again at 30%..is it plausible that (ruling out that i dont let it drop to zero, always charge at 30% and lowest 16% once in a while) and never charge to above 93% (only once in a while) mainly always take off at 70% cos it takes so long to charge i get impatient.. that effectively my battery capacity has reduced dramatically?i only got it in march manufacture date was jan 2014 and it’s only been warmer the past 2 months and that’s when i’ve noticed the dramatic reduction.. the annoying thing is there’s nothing i can do as there’s no fan to keep it cool, i already keep the case slightly open to let the hot air escape.. and also it’s incovenient being unable to use the phone when there isnt a fan source.
The reason I ask is for DIY EV applications the cost of the BMS is very expensive, and if the voltage was doubled with the same amps, the cost of BMS would be much less, half the cells to monitor.Why are lifepo4 individual cells only nominal voltage 3.2v? Isn’t this reducing the use-capacity of this battery quite a bit?I’ve read somewhere that a charger with a lower voltage rating (e.g., 3.2v) cannot recharge a lithium battery with a higher voltage rating (e.g., 3.7v). It would be nice to see charge efficiency as a function of time added to Figure 3 (or figure 1). And be safe? That would be like saying a garden hose is rated for seven gallons. It can provide power for an electronically controlled vehicle like golf carts.Therefore, it is equally important to care for your lithium-ion batteries the same way you care for a regular car battery. I bought a charger on ebay (it was very cheap) and it charges very slowly. NiMH batteries have the edge over lithium-ion batteries since they will often last for several thousand load cycles. I would like to attach the Mod battery to the phone when the internal battery is at 80%. The charging output of a USB is very adaptable to the charging condition of Li-ion batteries.Here are the steps and procedure in using the USB as your charging device.If you are interested in learning about this specific topic, then Lithium-ion batteries are commonly used in smartphones, tablets, and other electronic gadgets. You could check the voltage of the cell with a voltmeter.I’ve read quite a bit on Battery University and I think this is an excellent resource. Unfortunately I have not been able to reach anyone at Motorola that understands or can advise me regarding this issue. How do you know its’ “empty”? Better for the longest runtime the next time you need it? A high quality charger that is strong enough to charge your smartphone, notebook, etc. If you are planning a trip, then put it in and top it off before you go. This to me reaffirms how crucial it is with Li-batteries that the voltage should not fall below this. Therefore, no, I don’t see any need for any type of charge termination.If your battery voltage goes above the charging voltage, then current could reverse, backfeed into the charger, and drain the battery pack. Iv only seen low voltage alarms. A 1000mah battery would have a C rate of 1000maThe following statement involving temperature is has no relation to the C rates.Brad T, that post of yours is really opaque - on the one hand you seem to agree that the reference to C has nothing to do with degrees Celsius and actually refers to battery capacity. Enjoy!What i have believed is keeping my laptop plugged in all the time at my desk and using the battery power in case of power failure or so does no harm to my battery pack. But if you are drawing more than the cord can supply, then the phone is drawing from both the cord and the battery. You can get it here: http://www.amazon.com/PPUCLIP-Universal-Charger-Adjustable-Contacts/dp/B001RGYZJS If the PPUCLIP will charge the battery, but you phone won’t, then it’s a bad phone. v1 and v2 are corresponding voltage drops. (that is the reason why my laptop battery is absolutely dead after 4 years)@Dan Thank you for the reply! The chargers usually get their power from a cord rated at 5V, 1000 ma current.how to boosted fairly new sleeping li-ion ultrafire.I’m building a small battery operated radio powered by a 18650 3000mAh (supposedly).I’ve hit the problem of leaving the radio switched on while on charge because, as your article says, the charger may never “see” a current below the termination value and may continue to charge (at Stage 2).I’m wondering if devices which do allow themselves to be powered while charging (phones, ipads etc) simply rely on using only enough current to allow the charger current to drop below the threshold or if they use some other method of not “confusing” the charger.LiFe 3.3v LiIon 3.6v LiPo 3.7v, there is a difference between lithium ion and lithium polymer batteries. If you could find an app that limited charging to 75%, then you could leave it plugged in all the time. The worst thing that can happen to a lithium-ion battery is to have a full charge and be subjected to elevated temperatures. )Probably 4.2V, and also limited in current. Repeat each morning, and you may find yourself free from charging cables! Based on your article, it seems to me I should limit charging to 40 - 50 % when I’m not using it and try to get by with a 70% charge to maximize the service life. You reply via email, or don’t? What is wrong? One is rated at 9.6v and the other is 12.8v. But once it is fully charged, a smart charger will stop charging all together until the voltage drops down to a predetermined “switch back on” level, maybe 4.0v for example. Arriving at 15% I turn it off, I connect and gives me a 50% !! However, if a cell is shorted there wpuld be excessove voltage on the other cells in the series string. Maybe she should be the one writing the articles!I have a Toshiba C655-S5056 laptop with li-ion battery. So the battery will always be kept very close to full, so it’s ready when you do need to use it. I am seeking some safety information for these types of batteries. You may want to see if you can find, possibly from the manufacturer or elsewhere, a different type of adapter. Unfortunately, I say this NOT because I have any answers, but because after reading this entire page, I have very similar questions. This is actually it’s strength, that it can maintain close to its nominal voltage throughout most of its discharge cycle. I suspect the three discharge/recharge cycles may be allowing the phone to learn better what the battery’s true capacity is, and thereby reporting it more accurately.I think the only way to know for sure is to make some device that draws a consistent amount of current from the battery, say 100ma, and you time exactly how long it takes the battery to go from 4.2v to 3.2v, then completely charge it back up again, and repeat the test three times. when i charge again at 30%..is it plausible that (ruling out that i dont let it drop to zero, always charge at 30% and lowest 16% once in a while) and never charge to above 93% (only once in a while) mainly always take off at 70% cos it takes so long to charge i get impatient.. that effectively my battery capacity has reduced dramatically?i only got it in march manufacture date was jan 2014 and it’s only been warmer the past 2 months and that’s when i’ve noticed the dramatic reduction.. the annoying thing is there’s nothing i can do as there’s no fan to keep it cool, i already keep the case slightly open to let the hot air escape.. and also it’s incovenient being unable to use the phone when there isnt a fan source.