After doing some research, it seems as if the Energizer L91 batteries (sold as Ultimate Lithium) will work to power Hexy.
Can somebody please confirm? The spec sheet can be found here: http://data.energizer.com/PDFs/l91.pdf
A new pack of 4 has a total voltage of 7V, that should be fine? Seems as if the current rating is 3000mAh (judging by the Discharge Profile graph on the spec sheet, also: Max Discharge: 3.0 Amps Continuous).
thanks,
Johan
4 of these should be okay, as the voltage should be 6v (not 7v). Just make sure not to use 5, as that will blow the servos.
Thanks for the confirmation. A new set measured 7V (each battery obviously coming in at slightly higher than 1.5V), what is the maximum that the board can handle?
I’'ll use Duracell alkaline batteries whilst building and calibrating the legs.
If you are reading 7v, I would not use it then. The upper bound is 6v. Our guide on powering hexy is here:
arcbotics.com/products/hexy/powering-hexy/
Some feedback for others that may want to use these batteries as well, they are working just fine.
I’ve replaced one initially with an alkaline battery until the voltage for a full pack (of 4) dropped to about 6.5V.
A bit late to mention it, but if you are reading 7V unloaded it may be fine under load. Joe, can you suggest a resistance value to simulate a load? Or would connecting them just long enough to get a reading be OK?
Being motors, its not really a linear model-able resistance. That said:
V=I*R
R=V/I
We usually see 5amps peak at 6v?
R=6/5 = 1.2ohms max
And standing still is about 0.1amps
R=6/0.1 = 60ohms
So between 60ohms and 1.2 ohms? That’s coming kind of out of thin air though, so take it lightly.
Sounds like a 50W RF dummy load (50 ohm) might just do the trick for simulating a load to check battery terminal voltage then, don’t you think? As the current increases I would expect terminal voltage to drop more, so if we are seeing 6V or less with the dummy load we should be good, right.
Anyone tried these batteries yet?