batteriescertificationlithium ionspecifications
Hei,
Wondering if any of you have experience on secondary li-ion batteries (not battery packs) that comply with IEC 62133 certification?
I can't seem to find abundant amount of batteries covering such certification. Can you lead me in a right direction where to buy such batteries?
I have only found this which seems to have passed by IEC 62133:
Lithium 14500 Rechargeable Cell: 3.7V 800mAh (AA size, 2.96Wh) – IEC62133/UN38.3 Passed
Capacity should be above 1000mAh and max package 18650.
3rd terminal:
The 3rd terminal on your battery is most likely to be an "on board" thermistor temperature sensor. Try this.
Determine -ve and +ve battery terminals.
Connect ohm meter between -ve and terminal that is not +ve.
Blow warm air over battery (NOT TOO HOT) and determine whether resistance varies with temperature.
Sensor could be comnnected to +ve rather than -ve but -ve connection probably most likely.
Charging:
There are many ICs available for charging LiIon cxells.
If you want to build your own Lithium Ion / LiPo charger for up to 500 mA charge rate then using the MCP83831 / MCP83832 charger IC is a very easy and economical way of doing so.
This is eg what Sparkfun use in the LilyPad Simple.
Data sheet here
It can literally be as simple as shown in the circuit diagram below.
.
The resistor from Vss to Prog sets maximum charging current.
Several other options are available by selecting variants of the basic device. Unfortunately 3 different options are selected as a group (see datasheet page 21) providing less flexibility , but the device is still useful and well priced.
Options include cell voltage below which charger goes into "precondition" mode,
end point current termination level
and i_condition / i_charge ratio.
My main "complaint" with this IC is that the lowest voltage output level version is 4.2V and higher voltage (and very dangerous) versions are available.
Digikey sell 3 different versions (AC, AT, DC) with the AT mainly stopping charging sooner (longer life, lower capacity), while the DC variant will try to produce 'magic smoke' and 'vent with flame' if a very low voltage battery is charged.
Available in stock from Digikey for $US0.68/1 and $US0.42/100.
Cells in devices that you do not wish to be a flaming ruin MUST have protection.
Having protection circuits does not guarantee it will not happen.
Cells without protection are intended for use by either manufacturers or experts or enthusiasts who add their own or for suckers.
Whole device protection and cell protection are complementary and serve overlapping but different roles.
4,000 mAh 18650 LiIon batteries are ~~~= 99.9% +0.1% - 0.0% sure to be rubbish.
ie not just < 4000 mAh but << 4000 mAh and low quality.
The people who bogus label cells
almost never feel an obligation to use the best cells they can and
almost always decide to add injury to insult by using junk as well as lying.
Real world experience shows that the value of 'almost' is very high in both cases.
Higher capacity cells can usually be fitted OK.
MUCH higher capacity will lead to long CC tails and overcharge but not an issue here as mAh_new is < to << 4000 mAh.
Notice that in this ad and all their other ads they ALWAYS show non-brand-label views of the battery.
However, you may find that the racing stripes and general colour scheme a good match for the well known "Ultrafire" brand batteries. This may in fact be a real brand and these may be real examples of it BUT you can buy empty shrink wrappers to apply to the battery of your choice with this (or other) branding on it , so caveat emptor. Better nullius emptor I'd hazard.
These ones are a stunning 6800 mAh - a steal at the price. Available here
You'll find others similarly arrayed here and
here - 3000 mAh and 4000 mAh and
and unspecified but with GENUINE CREE 2000 lumen {so 20+ Watt} flashlight for $9.27 and
only 4000 mAh and
that's better - 4200 mAh
and .............
Flee!
Best Answer
Go to Farnell site, and look for Varta battery packs. Most of them have IEC 62133 as well as UN38.3 and of course RoHS.
Now the catch. You can buy IEC 62133 cells (not packs), however I assume you are gonna put it to some medical devices. That won't be accepted unless you have a battery protection board (PCM) and a thermistor integrated to the cell.
If you do the integration on your own, you have to re-certify the cell+PCM to IEC62133. This is 4k USD at least.
Therefore it may make sense to actually buy packs, not cells. You may prefer well known brands over some 3rd party panasonic-official-cell-integrator lab in a chinese garage.