I was just wondering about something. Are you guys considering to sell Li-Ion batteries and chargers on lynxmotion? They are much more dense than the Ni-Mh batteries you currently offer. They are also far smaller and lighter. There are Li-Ion 3.7v @ 2Ah cells that weigh about 35g.
Your current offered 7.2 Volt Ni-MH 1600mAh Battery Pack is 5.7oz =/ Running two Li-Ion cells in series can give you 7.4v @ 2000mAh for only 2.5oz. That is ~42% of the weight. The battery would be about 2 x 2 x .4". And lower mAh capacity can be even smaller.
This is just a though. You can totally disagree, I’ll understand. I know batteries are a #1 thing to think about and their size and weight limits projects, especially bipeds.
I still consider LiPo a risky product to carry. Lithium Manganese is much better than LiPo, but the expense will keep it from our site for a while. NiMH is still the cheapest safest battery solution for us, for now anyways…
Whoa! Thanks for the rapid reply I wasn’t expecting it until tomorrow mornin’.
I see. Thought that would be the reason. Ni-MH is very safe indeed. But isn’t it the user’s fault for stabbing the battery with a knife or screwdriver, or over charging it.
Thanks for letting us know though
Of course there are. I just like to order from a single place to reduce shipping costs.
My specs were based off of the larger batt on sparkfun. They are 2.1 x 2.1 x .23" i believe, not 2 x 2 x .2".
Over charge is not as dangerous as over-discharge. Lipos have become much safer than when they first hit the hobby RC market. They now have cell balancers and smart chargers. I use a monster lipo on my hobby bot (3100mAh 4S). Last time I charged it as April. Since I’m restarting my project I pulled the bot out and checked everything … still has 14V.
Depends on the current draw of the servos and the capacity of the pack. 20 servos on an AH3-R with pan and tilt will draw considerably more than a 20 servo biped. Lipo’s are no different than NiMH’s concerning capacity. You just can’t run a Lipo dead that’s all.
Another difference is the discharge curve of a LiPo and not to mention the power to weight ratio. I like the slow/non-existent self discharge and the light weight. I have the LiPo chargers from my RC aircraft days so choosing LiPo was easy.
Yes of course Lipos have several advantages, I was only refering to the capacity. Lipo’s deliver current based on their capacity in mAh just like NiMH batteries.
I wasn’t expecting it until tomorrow mornin’.