indyrcpilot

I just picked up my GP Triton charger yesterday and read the
instruction manual last night.

In the instructions they indicate that the charger will only charge
Li-Ion packs, not Li-metal or Li-Poly because they have different
charge requirements???

Check out "Care and Handling of Li-Ion Batteries" on Page 4.
http://www.electrifly.com/manuals/gpmm3150-manual.pdf

I thought that Li-Ion and Li-Poly had the same charge require-
ments. I bought the Triton so I could use it to charge my Kokam
1020 Li-Poly packs for my mini-IFO.

Can anyone on the list shed any light on this?

Thanks!
Chuck in Indy

fishgod

My Feedback: (13)

From my understanding Li-ion and Li-Poly have the same charging characteristics. With that said, I have been charging Li-Poly cells for a month and have had no problems at all. It works great. I have charged 145mh, 560mh, 950mh, and 1020mh batteries. I hope this helps

RocketRob

My Feedback: (1)

How is the trition working out with the Kokams?
This is an email I received after calling the factory tech. Seems the contraversy is around the trition's 3.7v cut off and the kokam's preferred(?) 4.2v cutoff to trickle......

Thank you for your recent email. Please find listed below the answer that
I received
from reserach and development.


The Triton charger WILL charge lithium-ion and lithium-polymer batteries.
This is a fact. The reviewer in question had an issue with exactly HOW the
charge process worked. Sorry, there is no short way to explain this.

Lithium-ion and lithium-polymer batteries must be charged using a "constant
current / constant voltage" technique. This method first has the charger
delivering a constant current to the battery for a period of time until the
MAXIMUM CELL VOLTAGE has been reached. At that point, the charger removes
the constant current and applies a constant voltage to the battery. Under
constant voltage, the battery itself - NOT the charger - dictates how much
current will be taken from the charger. As a lithium-ion or lithium-poly
battery becomes fully charged, it naturally restricts the flow of current
from the charger to a very low level (usually under 200mA). Once the
charger detects this low current, only then will it stop charging the
battery.

Triton's lithium setup has a maximum cell voltage setting of 3.6 volts per
cell. The on-line reviewer is of the belief that this voltage should be
higher, around 4.1 volts. This is the only difference between what Triton
actually does and what this reviewer prefers - it switches from constant
current to constant voltage at different times. This is NOT the same as
saying the charger stops charging lithium batteries at different times.

Lithium-ion batteries in particular are much more dangerous than NiCd or
NiMH batteries. For safety reasons, when charging lithiums we simply
preferred to have Triton stay in the "constant current" mode for a shorter
period of time than this reviewer prefers. This way, the battery is not
forced to accept the higher current if it is not needed. Having Triton
stay in the "constant voltage" mode for a longer period of time is safer
(and less stressful on batteries) because here the battery is allowed to
dictate exactly what it can or cannot take.

We've found that Triton might work a little better with higher capacity
lithium-ion and lithium-polymer batteries (in the 1200-1800mAh range) than
the smaller capacity batteries (like 600mAh batteries). Since the use of
lithium batteries is still very new to the R/C market, we, as are all other
charger manufacturers are trying to refine the best way to make lithium
chargers that best suit our application.

If you have any more questions, please do not hesitate to contact Great
Planes.

Thank you


Bill Thompson
Hobbico
R&D Electronic Designer
3001 Research Rd Suite B
Champaign Il. 61822
217-398-3630 x790
[email protected]