Develop Bugs

[Q] How much ampere does a Androidphone need for charging?

Hi,
I'm thinking about getting a bike-charger for my Androidphone and was wondering how much current would be necessary for an average device to charge or at least not drain?
The charging-device I'm currently looking at gives out about 300mA.
The reason why I don't state which Androidphone I'm using is that I want to future-proof my bikecharging, I don't want to get a new charger when I get a new device. Of course I'm not talking about a tablet.
Could someone edit the title of the thread to "[Q]How much ampere does a Androidphone need for charging?"

most android phones (at least most smartphones today) require 5volts at anything from 500mA to 1A for charging. Even if you supply them with 300mA they will charge if they are in standby but may actually drain under heavy use. You only have to respect the voltage rating - 5Volts. And i recommend at least 500mA, just to be sure.
If you need to build it from scratch.. you may need a dynamo attached to the bike's wheel. A bike dynamo will give you variable voltage/current. You need to regulate the flow of electricity from the dynamo to the phone, otherwise you risk killing the phone due to temporary spikes in voltage from the dynamo. An easy fix would be to use a LM7805 voltage regulator (available at electronics store, radioshack etc). It costs a couple of cents, and it will output a steady 5Volts if you supply it with anything ranging from 6 to about 28 volts.
Also check if the dynamo is supplying continuous or alternative current. If it's alternative, you need to use a rectifier bridge (also available at radioschack) to rectify the alternative current to a continuous one. A small 5 amp bridge should be enough. So.. your setup should look like - bike dynamo ->rectifier bridge ->lm7805 voltage regulator -> phone usb connector.
Have fun

Thanks for the info! I think I'll then have to go with a device that gives more ampere than just 300 mA - mobile data, gps navigation & music playback is what I'd classify as "heavy use", and that's what this whole setup is for
Also thanks for the update about all the extra equipment - I'll probably just go with all-in-one package, I know nothing about electronics

facdemol said:
most android phones (at least most smartphones today) require 5volts at anything from 500mA to 1A for charging. Even if you supply them with 300mA they will charge if they are in standby but may actually drain under heavy use. You only have to respect the voltage rating - 5Volts. And i recommend at least 500mA, just to be sure.
If you need to build it from scratch.. you may need a dynamo attached to the bike's wheel. A bike dynamo will give you variable voltage/current. You need to regulate the flow of electricity from the dynamo to the phone, otherwise you risk killing the phone due to temporary spikes in voltage from the dynamo. An easy fix would be to use a LM7805 voltage regulator (available at electronics store, radioshack etc). It costs a couple of cents, and it will output a steady 5Volts if you supply it with anything ranging from 6 to about 28 volts.
Also check if the dynamo is supplying continuous or alternative current. If it's alternative, you need to use a rectifier bridge (also available at radioschack) to rectify the alternative current to a continuous one. A small 5 amp bridge should be enough. So.. your setup should look like - bike dynamo ->rectifier bridge ->lm7805 voltage regulator -> phone usb connector.
Have fun
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Click to collapse
Now that is a helpful and informative post! If only more members were this decent

Whatever operating system it uses, it will roughly use the same amount of power.
What I did for my winmo Toshiba is to get 12......yes TWELVE rechargeable AA batteries, two 6 AA Battery holders, a plastic hobby box to house everything in, a samsung car charger (12v - 1amp max). I connected all the AA batteries in series. Then using the innards of the car charger, connected it to the battery terminals. The car charger works from 8v - 24v. When the rechargeable batteries are about to die, they go to 1v, so the car charger can still get the most from the batteries. I made a holder in my bike and this has been powering my phone It's awesome really as under testing with my old O2 XDA Orbit, the battery lasted for atleast 18 hours..... with a gps application running, screen brightness on full, music playing full whack, bluetooth on and wifi on!!
On my bike, the battery pack lasts enough for a week of cycling which is plenty enough for me!! Better than a dynamo ;-)

How much ampere does a Androidphone need for charging?
I agree with facdemol except for one part of his reply. I believe he meant DC (direct current) and AC (alternating current). If it is AC then he is correct about the rectifier bridge being required to change AC to DC which a is a power source his phone can actuallly use.

Smartphone External Battery Pack Recommendations?

I've been looking into an external battery pack for my phone as a backup, partly because the phones I am considering buying in the very near future don't have replaceable batteries, and partly because a replaceable or even extended battery doesn't really guarantee I can get through a day.
My biggest fear and reason for wanting this battery is if I have little to no charge in the evening/night and can't manage to get a decent amount charged. Having a battery backup would make me feel more secure knowing I have something to keep my phone going even if I somehow end up away from a charger for an extended period of time, however irrational such a situation may be.
As such, I have been looking and found there are 3 different types of battery packs.
1) Built in Lithium ion (most common)
2) Replaceable lithium ion (ibattz mojo is the only example I can find)
3) AA based charger.
Now charger type 1 seems to be common, but overall the battery will lose charging capacity over time, not be replaceable, and will need to be tossed.
Type 2 and 3, the battery can be easily replaced, especially on the cheap. However type 2 can be smaller and slimmer, while type 3 has the benefit of using LSD NiMH batteries. For those who don't know. LSD is Low Self-Discharge in this case. A lithium ion battery dies every week or two just sitting there, LSD NiMH batteries can hold up to 75 or 85% of their charge even after a year of just sitting there.
Overall type 3 seems the most ideal. However there is another element. Some chargers have cables built in, while others have just a standard usb plug. At first I thought the USB plug was annoying and a built in cable made more sense. However after some thought, I realized the built in cables added too much bulk, and I found keychain cables, which make more sense. My favorite example of this, is the mojo treble keychain, which seems to do everything and then some.
So basically now I am looking for the best AA based charger that doesn't have any usb cable built in, just a simple full usb plug. The closest I can find is by energizer, but it has the plug built in on a super short cable that looks as if it would put undue stress on my phone if I used it.
However if anyone has any other suggestions, or reasons to recommend something else, I'd greatly appreciate any input. At this time I just want to find the most versatile option. I would also love to hear other reasons for why people went with options other than AA rechargeables for their battery packs.

dkkeo said:
Extend battery:
(1) first of all to see the instruction for use,
(2) choosing a charging performance good charger. Charging time, keep the battery clean, dry. Helpful hints: use a mobile phone to send a text message, playing games is the power consumption
Click to expand...
Click to collapse
Any reccommended battery pack for LG nitro???

I use Belkin External Battery pack, reliable,
my other mates bought cheaper made in china battery pack but after a month or so, they are already in the bin, the battery is damaged.

Charger considerations
Hi,
I need advise for the following:
Charger A (Li-polymer battery) output : 5V, 1A
Charger B (Li-polymer battery) output : 5V, 500mA
Device input: 5V, 750mAH (Li-ion / Li-polymer)
When using Charger A, some people comment that it will limit the current of 750mAH for the device and the device's battery should be fine since both the charger and device are at 5V. However, some people comment that this will shorten the battery life of the device since it will perform a 'quick charge' using 1A.
When using Charger B, some people comment that the device will draw more current than it can deliver and causes it to heat up and reduces the charger's life. However, some people comment that Charger B will extend the battery life of the device since it performs a 'slow charge'.
I also read that USB pins on the charger denotes if the charger is a PC or a dedicated charger. If it is a PC, the device will limit the drawing current. If it is a dedicated charger, the device will draw more current to charge itself.
I am confused as to who is right and which charger should i be using.
Can someone enlighten me ?
Thank you very much.

JefferyTeo said:
I use Belkin External Battery pack, reliable,
my other mates bought cheaper made in china battery pack but after a month or so, they are already in the bin, the battery is damaged.
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80%-90% external battery packs are made in China at present. Some of the brands make good batteries as well.

tsgan272 said:
80%-90% external battery packs are made in China at present. Some of the brands make good batteries as well.
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Click to collapse
yes most external battery packs are made in china ,so i prefer to buy them from china supplier online ,
with better price and more convenient .belowed is the websites i often bought from ,which is better .
http://www.kingsbuying.com/consumer-electronics/power-banks.html
http://www.dx.com/s/power+bank
http://www.banggood.com/buy/Power-bank.html

Can our phones charge safely from a 6V USB charger?

Like the title says, can the typical smartphone (I'm actually asking for Galaxy Nexus specifically) safely charge from a 6V USB charger?
I'm asking because I want to make an Altoids portable USB charger for my GNex during travels. I've Googled a few results with mixed results. Some people built such a charger with a 4-AA battery setup, which means there will be 6V in the circuitry. However, some people have added a 5V regulator to the setup, while some have not. Those that have added it, sometimes reported insufficient voltage to charge the phone.
Basically, do I need the 5V regulator to safely charge my phone in this particular setup?
I know I can buy such a charger that is mass produced, but I want the satisfaction of a DIY product and appear to be the coolest hipster geek with my Altoid charger

Use Ni-MH rechargeable battery. Their voltage is 1.2V each, resulting in 4.8V in total.
If you use 4 Ni-MH battery with 5V regulator, it won't work. Voltage regulators are only good for stepping down, otherwise there will be improper operation.

I never understood portable chargers...with no disrespect to the OP, why wouldnt you just buy another battery or two? They are smaller and easier to travel around with than a portable charger without the voltage risk of running out of spec.

tincbtrar said:
I never understood portable chargers...with no disrespect to the OP, why wouldnt you just buy another battery or two? They are smaller and easier to travel around with than a portable charger without the voltage risk of running out of spec.
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The spare battery idea is a good one but I think one of the drawbacks to that idea is how to recharge the spares once they are dead. Energizer, Duracell and a host of other battery makers sell rechargeable power packs for not a lot of money.
I would hate to see you build one and have it short and catch fire or damage your phone not to mention the acid leaks from discharged batteries.
Edit. Just saw this in another thread. I bet a lot of us have rechargeable AA's lying around or since the are fairly inexpensive it may be worth picking some up.
http://www.batteryspace.com/battery...ndbeltcliponoffpowerswitch-rohscompliant.aspx

tincbtrar said:
I never understood portable chargers...with no disrespect to the OP, why wouldnt you just buy another battery or two? They are smaller and easier to travel around with than a portable charger without the voltage risk of running out of spec.
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Click to collapse
No disrespect taken. Like the ol' fried chicken guy said, where would I suddenly charge my batteries once they're out of juice? I could throw a portable charger in the car, and then go buy some cheap AA's during traveling. If I'm out of country, my charger simply won't even work (I think), due to plug incompatibilities.
Mind you, I have a Verizon Gnex, so I could use all the juice I can get my hands on. Especially during vacations, I'll likely be using the GPS, camera, and various other travel aid apps (Yelp, for one) that would likely drain my batteries a lot faster than I could imagine.
Back on topic: The NiMh idea is a good suggestion, but then I'd only be limited to using rechargables. I've seen the link to that commercially made portable charger before, but my ultimate goal is to go the DIY route. Also, the description of that item has the exact problem I'm trying to tackle, so that one is no better than something I throw together from radioshack and some Altoid tins.

mengsuan said:
Use Ni-MH rechargeable battery. Their voltage is 1.2V each, resulting in 4.8V in total.
If you use 4 Ni-MH battery with 5V regulator, it won't work. Voltage regulators are only good for stepping down, otherwise there will be improper operation.
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Click to collapse
Some AAs are 1.2v, while most are 1.5v off the shelf now. It is possible to use a 5v regulator to make sure the voltage does not go higher than 5v to protect your device. If the voltage drops below 5v it will simply stop charging as you need at least 5v +/- 3% or so.
What would be better is if you bought a dc-dc step up converter. This way you can use a single lithium battery (3.7v) or about 3 AAs (4.5v). The step up converter will take that 3-4v and bring it up to 5v or higher (adjustable).
Here's a dc-dc step up converter (http://www.ebay.com/itm/1PCS-LM2577...682?pt=LH_DefaultDomain_0&hash=item3cca94d2ca)
These are what most portable chargers use anyway. They step up the voltage to probably 6-7v? then bring it back down to 5v with a regulator. The reason why they step up the voltage to around 6-7v is to maintain amperage.

http://m.samsung.com/us/mobile/cell-phones-accessories/ETC-CPK008GSTA
what about using one of these to charge the spare. Love mine.
Sent from my Galaxy Nexus using Tapatalk 2

I recently got this because I had a lot of spare eneloops lying around. In 90 mins I get about 20%. For whatever reason when the phone stops charging, I can plug it into my friend's One X and his phone will continue charging where as the Nexus will charge for maybe another minute and then stop, not sure whats going on there but otherwise its a very good product.
http://www.engadget.com/2009/11/12/eneloop-stick-booster-supplies-emergency-power-to-your-portable/

rptw said:
I recently got this because I had a lot of spare eneloops lying around. In 90 mins I get about 20%. For whatever reason when the phone stops charging, I can plug it into my friend's One X and his phone will continue charging where as the Nexus will charge for maybe another minute and then stop, not sure whats going on there but otherwise its a very good product.
http://www.engadget.com/2009/11/12/eneloop-stick-booster-supplies-emergency-power-to-your-portable/
Click to expand...
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I was about ready to jump all over that until $40 gave me a slap in the face
I really liked what I read, but I don't think I can justify $40 on it.

rice923 said:
I was about ready to jump all over that until $40 gave me a slap in the face
I really liked what I read, but I don't think I can justify $40 on it.
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34$ and free shipping on ebay, but i actually got it as a gift straight from japan

6V batteries can't make a voltage regulator give out 5V, let alone if you use 4,8V batteries (4x1,2V).
A Voltage Regulator needs to have its input 2,5V minimum above the output voltage (5V+2,5V=7,5V).
You'd be better off (and more stable using either 6 1,5v batteries (or 7 1,2v NIMH) and a voltage regulator.
If you are "too near" of the desired output voltage as soon as the batteries discharge a little the voltage will drop (specially if you use 500mAh batteries) and the phone will no longer charge. Better off being above voltage on the batteries. 6x1.5v=9v, after a lot of discharge,6x1.25v=7,5V will still make the regulator output 5v. (Also don't be "too far" above the voltage or most will be dissipated by the regulator).
You'd be better off using a DC-DC converter which will convert power in any form to the form you wish. Example= 1,5vx500mA=0,75W=5vx100mA (well, allways with some efficiency loss, but way less of voltage regulator).
I've seen different devices, at 5V, charging at different currents. My Samsung will require a minimum of 500mA to charge. My Nexus, with a 1000mA (1A) charger will still discharge (although at a much slower rate than when not connect). Even with the device poweroff you wouldn't be able to charge it with AA batteries.
Or EVEN Better. An external LiON rechargable 7800mAH battery that, fully charged, will charge my Nexus 7 two times

6 Volt Charger

Recently bought a camping lantern that runs on a built in 6v 4.5 AH lead acid battery. It also has a USB connector which is for charging cell phones. I initially thought that the USB would be giving off a safe 5v but on testing it turns out that it is 6 volts straight from the battery.
Is this safe to use occasionally while camping? Will that extra 1 volt kill the battery or is there some mechanism inside the phone to regulate that voltage to a safe level?

Good question....hope someone has the answer for you.
Sent from my SCH-I535 using xda app-developers app

executionist said:
Recently bought a camping lantern that runs on a built in 6v 4.5 AH lead acid battery. It also has a USB connector which is for charging cell phones. I initially thought that the USB would be giving off a safe 5v but on testing it turns out that it is 6 volts straight from the battery.
Is this safe to use occasionally while camping? Will that extra 1 volt kill the battery or is there some mechanism inside the phone to regulate that voltage to a safe level?
Click to expand...
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Of course there should be.You get more than 6v in a power socket around the house.

Gkikas said:
Of course there should be.You get more than 6v in a power socket around the house.
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No one plugs their phone directly to the wall socket :/ Thats what the charger is for, it only gives 5v to the phone. Just need to know if it can regulate that 6v to a safe level.
*edit. I think no one here would know about the hardware aspects of a phone. Can someone point me to a forum or anywhere where they may know the answer to a question like this?

May I asked how you measured this?
I'd love to check what output my 12v chargers are outputting

TieNN89 said:
May I asked how you measured this?
I'd love to check what output my 12v chargers are outputting
Click to expand...
Click to collapse
A multimeter and a stripped usb cable

executionist said:
A multimeter and a stripped usb cable
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ah yeah
My brain has already flicked off for the day LOL

if you use IRC, try the freenode server in the ##electronics channel. they should help you out there. pretty nice ppl in general there.
Sent from my GT-I9300 using xda app-developers app

?
I'm interested as well. Will 6 volts @ 500mAh fry the phone?

Ok, I am an electronic engineer so a few comments.
I have no idea what kind of charging circuit is in our phones, could probably look it up but ..... in my opinion only 10% above 5V is to be considered safe.
Now you are talking about a 6V battery. That battery is not always 6V. A nice example is the 12V battery in your car which is 12.8V when fully charged. Another example are the cells inside our phones which have a nominal Voltage of 3.7V but are charged to 4.2V.
The Voltage they put on those things is the nominal Voltage.
I would check if there is no electronic circuit in that lamp since I would not connect anything directly to a battery at all.
If you go camping I would check this thing coolook pb-2000. Insert 4 x 18650 batts and you can do a couple of recharges. Very good box for the price and you can salvage 18650 from broken laptop batt packs ... but google and youtube a bit before you do that to make sure you do it the right way.

I'm also interested, any news?

You can see the specs of this type of batteries here. The 6V is nominal, as already mentioned above. The maximum noted is 6.9V and TBH, i would be rather reluctant to test is my SGS3 charging circuit likes the idea of being fed with 40% higher voltage than usual.
Are you sure there is nothing in the lantern that would limit the voltage under load? Could be something as simple as 2 diodes in series, in this case measuring the voltage on the open circuit, totally unloaded, with a DMM that barely draws microamps from it, would show the battery voltage. Try drawing some current from it (use a resistor, a USB LED lamp, etc) while measuring. I seriously doubt a self-respecting vendor would setup a USB port on that thing that would potentially output 40% more than specs, really.
PS: if the port is, indeed, fed straight from that battery, i would rather avoid hooking my SGS3 to it. Even though, it would probably survive.
---------- Post added at 07:08 PM ---------- Previous post was at 06:59 PM ----------
lukesan said:
I have no idea what kind of charging circuit is in our phones...
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Click to collapse
MAX77686. Good luck finding the datasheet. And good luck trying to guess if there is anything else potentially fed straight from the USB connector. The bottom line is - i wouldn't dare

Solder this to red wire https://en.wikipedia.org/wiki/Zener_diode
OFC you need 5V model

GR0S said:
Solder this to red wire https://en.wikipedia.org/wiki/Zener_diode
OFC you need 5V model
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Click to collapse
Not if it doesn't have a resistor in series. And wait. if the battery is at 6.8 Volt and you have a 5.1 Volt zener and it is charging at 1 Amp so you will need a power resistor. You will have a lot of loss of energy because it will go away in heat.
You could use a dc-dc convertor but believe me forget about it and get one of those charging banks where you can put in your own cells.

lukesan said:
Not if it doesn't have a resistor in series. And wait. if the battery is at 6.8 Volt and you have a 5.1 Volt zener and it is charging at 1 Amp so you will need a power resistor. You will have a lot of loss of energy because it will go away in heat.
You could use a dc-dc convertor but believe me forget about it and get one of those charging banks where you can put in your own cells.
Click to expand...
Click to collapse
I'm not sure about how practical it would be to be cutting usb cables and wiring zener diodes just to use this lamp....
I think I had a charger that supplied too much voltage (I'm not positive I didn't measure the voltage output or anything), but I can say that the phone did not like it. It would eventually charge somewhat, but the touch screen wouldn't work and would go bezerk if touched lol.
Again I'm not sure how much V it supplied, but I would assume it was more than 6V. It didn't really damage the phones either, I would try it.

Here's your answer, definitively:
6v at the source (the lantern in this case) will probably be 5v or less at the phone because of the resistance in the USB cable itself. The longer the cable is the higher the resistance will be and thus the more voltage you lose to it. Also, the cheaper the cable (the thinner the wires) the more voltage you will lose per foot.
Here's some specs you can plug into THIS VOLTAGE CALCULATOR:
The USB definition specifies up to 5.3v.
Most USB cables will use 30awg wire or maybe 28awg for the better ones.
Depending on which of the sources I've read, some USB cables/chargers use one pair of wires for charging, and some will use two pairs. You can see that using two pairs of conductors drastically improves the voltage transmission but even still, at 28awg over a 6foot cable you're still losing .75v which puts you at 5.25v and well within the USB spec.
So the lantern is fine to use with your phone with your average 6-foot USB cord.
If you're like me and prefer 10-15 foot USB cords in some places you would actually benefit from a 6v or even 7v power supply at the wall. I've found that even on the OEM Samsung wall charger, when I use a 10-foot cable I don't get enough juice to actually charge my S4. With the screen on the battery charge level still drops. The Galaxy Charge Rate app shows something like 500ma charge rate and that's because there's not enough voltage / too much voltage-drop across the long cable. (Radio Shack sells a modular, adjustable voltage wall-wart power supply as well as USB and micro-USB adapters for it. I'm starting to experiment with it and the long cables.)

USB voltage vs charging current
This is an old thread, but I can confirm that my moto G charges at 6v. Apparently the original Motorola charger outputs 5.75v. I hooked up a variable power supply to my phone. The data lines are shorted together to indicate a high current power source is present. The moto G will test load the power supply before settling on a stable charging current. One that does not cause the voltage to sag excessively. When I applied 5v the charging current was approximately 600 mA. At 6v the charging current was approx 1200 mA. The charging current was measured directly on the phone using an app called ampere.
So I conclude that Motorola use this tactic to ensure their phones charge fastest with their chargers. On the up side, its fun watching my phone go from 40% to 100% in 45 minutes

[TECH DISCUSSION] Is it possible to have a Dash Charge power bank?

So I'm in my junior year of electrical engineering and seeing the incredible things done with smartphones is something I really would like to be a part of one day. I wanted to discuss, considering the limits of current technology, if it would be possible to create a safe Dash Charging power bank for this device? For those who don't know how dash charging works I'll post a few links and my understanding of how it works and if I'm wrong at any point feel free to correct me.
Dash Charging - The Technology
The way dash charging works, as I understand it, is that the USB-C cable wires are made wider in diameter to accommodate a larger amount of current being passed through to the battery. The charger plugged into the wall takes on the burden of the extra voltage pushing the current through the wire and keeping it away from the phone's internal battery (which is brilliant). That means that the charger takes on the extra heat which isn't a problem because passive components are often more tolerant of heat than batteries are.
Links:
http://www.phonearena.com/news/How-it-works-Dash-Charge-fast-charging-on-the-OnePlus-3_id82646
http://www.trustedreviews.com/opinions/what-is-dash-charge-oneplus-3
The Issues
A dash power bank could be charged up exactly like the phone; with the dash charger it could fill extremely fast. However, using the battery pack to charge the phone means that the internal Li-Ion batteries of that charger will be taking on the extra heat from within the case which could:
a) shorten the power bank's life span
b) Possibly lead to unsafe power banks if it got too hot
I also see there being limitations with the power bank's ability to maintain a full speed charge similar to wall charging along with what types of batteries would be needed to provide the power output similar to the dash charger.
The Solutions
So in my limited knowledge I think that the biggest enemy here is heat generated in the power bank. I feel like the rest could be overcome with a fairly large bank of 18650 batteries. It is possible to have a passive cooling system built into the power bank for heat dissipation but that might make the battery bank difficult for users to hold on their Pokemon Go outings. Also, reducing Dash Charging specifications just a little, decreasing the speed at which it could charge the device, would alleviate some of the concern. So while you might not get 60% in 30 minutes from the wall, perhaps aiming for 45-50% charge in that amount of time would increase the power bank lifespan and total amount of charges.
What do you all think? I'll readily admit I don't understand completely how current battery bank internals work to limit over-current and over-voltage scenarios as I've never taken one apart. If anyone wants to educate me and say whether they think Dash Charging is possible I'd love to hear about it. This is the kind of stuff I imagine the OnePlus engineers are sitting around working on every week.

i think that would be too expensive to make for consumers, u figure if a dash charge block is almost $30.00 this thing would be well over $500.00 which would be too much for a regular consumer to purchase just to have a portable charger, maybe in about the 3rd or 4th generation of this technology we could see one in about 5 years, they would rather make a ton of 30.00 purchases and have you buy their charge block opposed to very little purchases of about 500.00 for power bank

It's actually already there in the market,
named "OPPO VOOC Powerbank"
attached is mine, working fine with OP3 Dash,
Price is around $45-50 - 6000mAH
Charging rate is 3,5A
and it DOES charge my device up to 60-70% in 30 Minutes
it heat up though, especially near the plug (USB C end)
this is why i use the metal based USB C adapter, so it release the heat faster

otonieru said:
It's actually already there in the market,
named "OPPO VOOC Powerbank"
attached is mine, working fine with OP3 Dash,
Price is around $45-50 - 6000mAH
Charging rate is 3,5A
and it DOES charge my device up to 60-70% in 30 Minutes
it heat up though, especially near the plug (USB C end)
this is why i use the metal based USB C adapter, so it release the heat faster
Click to expand...
Click to collapse
I had no idea that even existed. I'm going to look into the specs of that device and see what it has under the hood. Thanks for letting me know about it!

AlkaliV2 said:
I had no idea that even existed. I'm going to look into the specs of that device and see what it has under the hood. Thanks for letting me know about it!
Click to expand...
Click to collapse
Here,
the information page from the maker itself :
http://www.oppo.com/en/accessory-vooc-power-bank
and where to get it :
https://www.amazon.co.uk/OPPO-VOOC-Flash-Charge-Power-White/dp/B00SINEEXA

I'm going to build power bank using Dash Charge car charger. The power banks higher voltage (12V if using car charger) means less current for individual cell while charging. I have bought battery holder case 10 x 1,5V for AA batteries. http://r.ebay.com/vpShFJ (I already have plenty of Eneloop AA batteries for other accessories.) Each Eneloop has at least 1,5Ah (1500mAh) capacity while retaining voltage at or over 1,2V. http://lygte-info.dk/review/batteries2012/CommonAAcomparator.php I'm going to attach 12V socket to the battery holder case so I can use my car charger both in car as well while at camping.
Battery bank consisting of 10 x AA Eneloop has a total capacity of: 12V*1,5Ah=18Wh.
Dash chargers input is rated at 12V/2.5A so each individual Eneloop would have about 250mAh discharge rate.
My old Galaxy Note 3 had 3,8V 3200mAh battery and the capasity was ~12,2Wh. I don't know the nominal voltage of OP's battery but I would estimate it's about the same as Samsung's so the capacity should be lower than in Note 3. Maybe around: 3,8V*3000mAh=11,4Wh.
10x Eneloop batteries has a capacity to give energy for charging OP3 from 0% TO 100% at least. (18Wh/11,4Wh = ~1,6)

I think in India it's not available
Sent From My One Plus 3

https://forums.oneplus.net/threads/new-product-survey-dash-charge-power-bank.457920/

Squabl said:
I'm going to build power bank using Dash Charge car charger. The power banks higher voltage (12V if using car charger) means less current for individual cell while charging. I have bought battery holder case 10 x 1,5V for AA batteries. http://r.ebay.com/vpShFJ (I already have plenty of Eneloop AA batteries for other accessories.) Each Eneloop has at least 1,5Ah (1500mAh) capacity while retaining voltage at or over 1,2V. http://lygte-info.dk/review/batteries2012/CommonAAcomparator.php I'm going to attach 12V socket to the battery holder case so I can use my car charger both in car as well while at camping.
Battery bank consisting of 10 x AA Eneloop has a total capacity of: 12V*1,5Ah=18Wh.
Dash chargers input is rated at 12V/2.5A so each individual Eneloop would have about 250mAh discharge rate.
My old Galaxy Note 3 had 3,8V 3200mAh battery and the capasity was ~12,2Wh. I don't know the nominal voltage of OP's battery but I would estimate it's about the same as Samsung's so the capacity should be lower than in Note 3. Maybe around: 3,8V*3000mAh=11,4Wh.
10x Eneloop batteries has a capacity to give energy for charging OP3 from 0% TO 100% at least. (18Wh/11,4Wh = ~1,6)
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Click to collapse
We're going to need a hardware XDA for people like you. I never would have thought to string together Eneloops to make an external charger since most of your power banks contain 18650 with overcharge protection and stuff built in. The wall dash charger is spec'ed to run 5V at 4A and the car charger loses half an amp to land in at 3.5A max. Car charger voltage varies between 3.4~5V from what I can tell probably based on the car's cigarette lighter specs.
What kind of case are you using with the eneloops and what are you using for overcurrent/voltage protection?

otonieru said:
It's actually already there in the market,
named "OPPO VOOC Powerbank"
attached is mine, working fine with OP3 Dash,
Price is around $45-50 - 6000mAH
Charging rate is 3,5A
and it DOES charge my device up to 60-70% in 30 Minutes
it heat up though, especially near the plug (USB C end)
this is why i use the metal based USB C adapter, so it release the heat faster
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Click to collapse
So... can you tell me if a normal VOOC charger block charge the OP3 as fast as the original dash charger in package?
I saw it is the same current rate, but the technology, is it interchangeable?

Just wait oneplus is planning to release a dash charge powerbank with 10000mAh so stay connected no need to buy oppo 6kmAh one

AlkaliV2 said:
The wall dash charger is spec'ed to run 5V at 4A and the car charger loses half an amp to land in at 3.5A max. Car charger voltage varies between 3.4~5V from what I can tell probably based on the car's cigarette lighter specs.
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Click to collapse
You are right, the car charger uses lower current and is probably a bit slower. When I receive my car charger I will do some testing and will report back.
The voltage variation is needed on all chargers. When the battery is almost full the charging voltage drops.
AlkaliV2 said:
What kind of case are you using with the eneloops and what are you using for overcurrent/voltage protection?
Click to expand...
Click to collapse
I have ordered a case like this: http://r.ebay.com/vpShFJ
The car charger has been designed to be used as it is. The charger itself does not require additional overcurrent protection but in case of a short circuit a 5A fuse is needed to protect the wiring and Eneloops. Overvoltage is not a problem as the maximum voltage with Eneloops is going to be under 15V.

DouglasDuZZ said:
So... can you tell me if a normal VOOC charger block charge the OP3 as fast as the original dash charger in package?
I saw it is the same current rate, but the technology, is it interchangeable?
Click to expand...
Click to collapse
Yes it is. I've posted it in another thread as eell. Just check through my post history.
This is pure logical, since Oneplus is just a subsidiary company of OPPO, so they surely can share few technologies between each other, and VOOC/DASH is one of it,
Just make sure your usb c adapter quality is good when you decide to use it with VOOC charger.