Battery chargers and amperage...

[ZaO]

I've done a bit of reading around looking at formulas to work out this out. But honestly, I get confused with numbers and electronics lingo sometimes. And the information doesn't seem to match across the different things I read. So I'm a little clueless here. But my question should be pretty simple for someone who knows a bit about electronics, I'm sure!

So basically, I have some batteries ranging from 150mah-280mah. The proper charger for them supplies 5v and 500ma. But I was hoping to speed up the charging of them by using a 5v/1amp charger. Am I at risk of damaging the batteries by doing this? Thanks

[TheAnimus]

Depends on the batteries!

You charge batteries by providing a current source, not a voltage source, so if you have a higher output of amps you can allow the battery to charge faster. However some batteries really don't like that, so yes, in theory having double the current available could let them charge twice as fast, or help them go pop and burn your house down!

What are the batteries?

[ZaO]

ah damn haha! :/

these are the batteries: http://jacvapour.com/batteries/v3i-batteries

and this is the charger for them: http://jacvapour.com/usb-to-mains-adapter-uk

not very detailed specs there i know! and i would ask that company. but i know for sure i'd just get a customer service agent with no electronics knowledge telling me something like "we only recommend you use the specified charger etc...". so i thought i'd try get the info elsewhere thanks!

[AETAaAS]

I just had a look. In this scenario, the limiting factor is not the wall charger but the regulator/adapter (circled in red) to which the batteries have to be connected. I am not sure if this is the setup you are using but I think it should be.



I am assuming it is this: http://jacvapour.com/usb-charger-for-the-v3

In the specs it says:
Input - 5v DC 500mA
Output - 5v DC 150mA

So using a higher amperage wall charger will not make it charge any faster because this adapter will only draw its rated amperage, and will charge your batteries at the rate you are doing now. Higher amperage USB chargers cannot push any more current through the adapter (as USB auto regulates current in most circumstances based on the device attached), so you are unlikely to damage the batteries by using your 1A (or higher) phone charger for example but it won't make things any faster.

[ZaO]

ah yeh. i didn't notice the adapter had it's own limit too! just had a look at mine. the input and output specs are the same as what you linked there. so i guess that's the choke there!

but let's say i had another adapter with a higher limit. what do you think about it then? any idea what would be a safe amount of mah to let through? thanks

[AETAaAS]

Someone else more familiar with these devices may know more than I, but my feeling is that your best bet is to get another similar charger/adapter. Going by the ratings, it should only take an hour or two to charge these batteries (capacity dependant), is it taking much longer?

Looking around, it appears your battery is of the 'KR808D-1' or '901' socket, and there are few chargers indeed. USB socketed ones are essentially the 150mA model you already have. The fastest being a 4.7v 200mA unit but usual caveat of 'looks right, no actual idea' applies.

[ZaO]

Someone else more familiar with these devices may know more than I, but my feeling is that your best bet is to get another similar charger/adapter. Going by the ratings, it should only take an hour or two to charge these batteries (capacity dependant), is it taking much longer?

Looking around, it appears your battery is of the 'KR808D-1' or '901' socket, and there are few chargers indeed. USB socketed ones are essentially the 150mA model you already have. The fastest being a 4.7v 200mA unit but usual caveat of 'looks right, no actual idea' applies.

yeh mine is using the 808 thread the charge time is about what it should be. but i was just hoping i might be able to speed it up a bit lol and thanks for the link. i'll have another bash at reading up on the rules about chargers and batteries! you made a really good effort to help me though mate. appreciate that! thanks

edit: i found something else. if this is right, and i understand it correctly. then it's pretty easy to figure out!

"How large of a charger should I have?
With limited knowledge of battery charging, one might believe that
a 400Ah battery bank, charged by a 400-amp charger, should fully
charge from a completely discharged status in about an hour.
However, a charger that large would cause so much heat build-up in
the battery that it would be completely destroyed before too long.
On the other side of the spectrum, a 5-amp charger would not
damage the battery, but would take over three days to charge! So ...
what’s the optimum charger? The general rule of thumb is C/5, or
Capacity (in amp-hours) divided by 5. So an 80-amp charger is the
right size for a 400Ah battery bank (400/5=80). When rounding is
necessary, always round down because your battery bank will
degrade over time and your C/5 rule will eventually meet."

so just divide the batteries capacity (mah) by 5. then the answer is the approximate amount of amp/ma you want going into the battery from the charger.

[peterb]

As the animus said, it depends on the battery. Some batteries, lead acid cells, such as car batteries, need a constant voltage source and there current they draw during charging is self regulating. Other batteries, such as Nickel-Metal hydride (NiMH) require a constant current source.

I suspect your batteries require constant current.

Battery capacity depends on the discharge rate, a 2000mAH battery might be quoted at the 10 hour rate, meaning it will supply 200mA for 10 hours, but it might only provide 2A for 30 minutes. It might provide 20mA for 200 hours.

Batteries should generally be charged at the capacity/10 so a 2000mAH battery should be charged at 200ma for at least 10 to 12 hours. however you can charge them faster, but you need to monitor the charge time carefully to ensure you don't overcharge them. In extreme cases the battery could explode because of heat build up.

Good fast chargers monitor the battery voltage (and sometimes temperature) to ensure that batteries are not overcharged, although fast charging will probably reduce the life of the battery anyway.

If you want to leave batteries on charge, the charge current should not exceed 1/10 of the capacity - so for a 2000mAH that should not exceed 200mA.

There is a good article here.http://www.powerstream.com/NiMH.htm

Just to re-emphasise - fast charging batteries without using a specially designed charger, or monitoring charge time carefully is potentially hazardous, leading to the risk of overheating, and in extreme cases, causing the batty case to burst.

[ZaO]

Thanks mate. That's very informative! I will check that link in a minute. But this info leads me to think I should just stick to using official chargers as I normally do. Looks like it can get quite specific. So unless I want to do a lot of reading up, that's probably the best idea for me! Thanks

[peterb]

Thanks mate. That's very informative! I will check that link in a minute. But this info leads me to think I should just stick to using official chargers as I normally do. Looks like it can get quite specific. So unless I want to do a lot of reading up, that's probably the best idea for me! Thanks

Yes - probably safer - and you can always get a couple of extra batteries so you always have one charged and ready to go. The site didn't give much detail, but if they are standard AAA size, the technoline BL700 charger is a very good charger that will give you safer fast charge rates.

http://www.batterylogic.co.uk/techno...line-BL700.asp

Its bigger brother, the BL1000 will give even faster charge rates, but at the expense of much reduced battery life (and it costs more!)

http://www.batterylogic.co.uk/techno...-i-charger.asp

[watercooled]

I suspect they're Li-ion batteries, but just to re-reiterate, it all depends on the batteries. You can get some RC Lipo batteries which will happily accept a 10C (basically 10x the mAh rating) or greater charge current for very rapid charges, and often even faster discharges e.g. 120C so flat in 30 seconds!

OTOH, some Li-ion cells are plain dangerous to charge faster than 0.5C (or half the mAh rating). So without knowing exactly what sort of cell is being used inside the battery pack, yeah you are at risk of damaging the cell, and whatever happens to be close to it. Li-ions can behave quite violently if they're mistreated, and the smoke they release is also quite toxic.

Something else to note, 'forcing' more charge into a given Li-ion battery might not charge it that much faster anyway. They're charged with the CC/CV, or constant-current then constant-voltage profile. Higher constant current can mean the battery finishes that stage faster but will take longer than normal on the CV ramp to reach 100%.

That adapter should not be merely a current limiter, and considering the batteries are still in one piece I'd expect that to be the case. A proper Li-ion charger will (as above) charge at a set current, then when the terminal voltage matches the supply voltage (usually 4.2v depending on the chemistry) the current will essentially self-regulate and continue to ramp down as the cell itself comes up to meet it. Then the charger should terminate at roughly 1/10th the starting current. Li-ions should never be float/trickle charged (which is also why advice to leave your phone on charge for 14 hours or so for the first charge is false, and left over from the days of NiMH phone batteries - the phone's Li-ion charger will automatically terminate the charge when the battery is 'full', so leaving it plugged in is pointless).

Batteryuniversity is a good site for this sort of information if you're interested.

[peterb]

I suspect they're Li-ion batteries, but just to re-reiterate, it all depends on the batteries. You can get some RC Lipo batteries which will happily accept a 10C (basically 10x the mAh rating) or greater charge current for very rapid charges, and often even faster discharges e.g. 120C so flat in 30 seconds!

Yes, but to get that rate you need a charger specifically for that, and that charger will monitor each cell during the charge process (and ideally discharge each cell individually to ensure that one cell isn't overcharged) LiPO batteries have high energy storage densities, and when they go pop, they go with a vengeance - which is why it is recommended that they are fast charged in a fire resistant bag outdoors on a non-flammable surface! It would add a new dimension to vapeing

[watercooled]

Exactly. The RC packs (at least the multi-cell ones) tend to have balance leads to connect to the charger for precisely that reason. Discharging or cycling isn't necessary for Li-ion though, and can do more harm than good - but if a cell is out it can be held at a given voltage (essentially diverting away the charge energy) until the others 'catch up', depending on the type of charger.

Edit: I wasn't suggesting the OP use an RC LiPoly for an e-cig BTW, I was just demonstrating, even knowing the chemistry doesn't tell you the whole story. A LiPoly could make for one heck of an e-cig though xD

No seriously though, don't do it...

[ZaO]

ok guys haha i'm gonna get lost in the technicalities here! but feel free to discuss! though i have decided that i just don't know enough. and so will stick to just using the chargers that come with batteries. i think it'll be a good idea just to buy a second charger and keep a little rotation going. so that's what i'll do

[Andson]

I guess the charger will change another way to wireless charger. As the technology is developing so fast. wireless conception maybe a new trend in the future. So I guess many big company will release more and more wireless product. Like htc has one mobile phone can use wireless charger as well as Nexus. So maybe Apple, Samsung, or MOCREO such companies will release new wireless charger.

[gautampal]

By using Portable USB Charger recharge your mobile, smartphone anywhere and anytime.