12V DC Rechargeable Li-ion Batteries... Charging Time Issues :(

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So I bought these batteries a while ago:

12V DC Rechargeable Li-ion Battery for CCTV Cam 9800mAh
Capacity of battery: 9800mAh
Input voltage: 12.6V
Output voltage: 12.6-10.8V



12V DC USB 5V Rechargeable Li-ion Battery
DC input: 12.6V
DC output: DC12.5V~10.8V
Rated current: 1000ma
Capacity：3800mah
Gross weight: 355g


Now the thing is I get quite a bit of use out of the smaller 5V/12V batteries (3800mah), and running from the 12 volt it can power a HDV-Z96 LED light (96 LEDs/800Lx/7W/5.8-16.8V Input) for just under 2 hours at full power... not bad! I Velcro them to the back of the Z96... works like a charm!

The larger 12V (9800mAh) will run the same light for between 7 1/2-8 hours straight through on full power! (but it's heavy to carry around and I have to run a longer cord to where the battery is supported)

All in all for the price they work great and I'm happy with them... EXCEPT: They take FOREVER to charge with the supplied charger! The green light goes out on the 3800mah indicating a full capacity charge after about 8 hours charging (for 2 hours runtime) while the green light has NEVER gone out on the 9800mAh battery, not after 24 hours charging, nor 36 hours charging... so I don't really know when it hits its full charge... 24 hours seems to do it though. (for 8 hours runtime)

I'm thinking the charger it comes with is inadequate, and I would like to know if I could increase the output of the charger from 12.6V DC 350mAh t something higher to cut the charge times by at least half? What can be done?

[Janke]

Li-ion batteries are a bit finicky about how you charge them - if they don't like what you do, they explode on you...

Battery charging procedure

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Li-ion batteries are a bit finicky about how you charge them - if they don't like what you do, they explode on you...

Battery charging procedure

Hmmm... so... I should charge them at a higher mAh?

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Wow, be careful there.

You have a battery pack.

You have a power supply.

The thing you are plugging into the wall socket is a power supply, NOT a charger!!!

It is possible that the correct charging circuit is built into the battery pack though, but without opening it up, and checking it out, you'll never know.

But yes, you SHOULD BE ABLE to use a higher amperage power supply to charge them faster, PROVIDING the charging circuit is built into the battery pack, and that circuit allows for higher charging rates.

All unknowns unfortunately.

If you do attempt to charge them faster, I'd do it outside in a remote location; something like a fire brigade training facility, and remote switch it on and observe it via a CCTV from another town!

Edit: Oh, I see the green light now in the pictures. So it appears to be a charger after all!!
That's good but I wouldn't trust them.
There still should be circuitry to balance each of the three or six cells.
Very low amps for the size of the battery though.

How much did you pay for them?

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How much did you pay for them?

$38 Free Shipping For The 12V 9800mAh
$19 (Each) Free Shipping For The 12V 3800mah (5800mAh @ 5V)

Oh, I see the green light now in the pictures. So it appears to be a charger after all!!
That's good but I wouldn't trust them.
There still should be circuitry to balance each of the three or six cells.
Very low amps for the size of the battery though.

The same charger came with BOTH the 3800mah and the 9800mAh batteries... the (online) info on the 3800mah says its rated current is 1000mAh, so I figure you could go a LOT higher than 350mAh!

Here is the info that came with them:

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Yeah, that's pretty cheap!!

If you're VERY careful, you could try a li-ion charger (3 cell) from something like batteryspace.com:
http://www.batteryspace.com/Smart-Ch...tery-Pack.aspx

That should handle both packs. Not sure what size the pin is on your device, but 2.1mm and 2.5mm are the most common.

That's of course assuming that the battery cells aren't LiFePO4, which I doubt.

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By 'very careful' I mean that you try it where if something goes wrong, you & surrounding are safe; i.e. on
concrete floor with fire extinguisher handy.

My best guess is that the charger I linked to is okay though.
Check for increase in temperature of the battery pack. If it gets hot, stop charging.
Getting only warm should be okay.

My other best guess is they didn't include such a
charger because it would have increased their cost too much, and as such wouldn't be able to sell as many as they now have to charger 20-30% more.

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The pin is 2.1mm... I know this because I had to build 6 cables (various lengths) that went from 2.1mm on the battery end to 2.5mm to use with my Z96 and my other 5.5/2.5mm barrel devices.

Yeah that charger looks perfect! The batteries share an input/output port, to charge you plug in the provided charger, and when you turn the battery "on" the green light comes on, then shuts off when capacity is reached (on the 12V/5V ones anyway, as mentioned the green light has never turned off when charging the 9800mAh battery).

Too bad they want $21.00 more for shipping to Canada I'll have to take a look locally...

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That's of course assuming that the battery cells aren't LiFePO4, which I doubt.

Shall I dismantle one for you? I wouldn't know what to look for anyway...

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Nah, it's almost certainly NOT LiFePO4: that isn't quite as dense (energy/volume) and they tend to be more expensive.
(They are safer though!).
Your pack is likely to be either LiIon cells or Li-Poly cells. This is also coinciding with the supplied 'charger' - 12.6 V indicates end-voltage
of three Li-Ion/Li-Po cells, NOT LifePO4, which has different voltage characteristics.

Both Li-Ion and Li-Po can be charged with the linked charger.

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Both Li-Ion and Li-Po can be charged with the linked charger.

Great! Thanks Mal! Now can you help me find one for that price (from China) with free shipping to Canada

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LOL, actually I have some here (although less amps, I believe something like 1amp, or 0.5amp), but shipping.....ouch!!!

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I guess the more amps the faster the charge huh... I might be worth the $48 shipped? Hmmm?

[Mark G]

I always stick to the proper charger that comes with a device, however, I have a rechargable LED shop light. Somehow I mixed up the charger than came with it and another one I had around from some other device. Same size, same plug in, but different outputs. The one I had been using for the last 2 years was about 18% higher output. Anyway, when I ran across the original one and started using it, it took a noticably longer time to charge. But, I never notices any detrimental effects by using the more powerful charger.