Battery Basics for Robotics - Everything you Need to Know!

If you're getting interested in combat robotics (or robotics in general) you're going to need batteries and you'll need to know how to use them and understand the various ratings and specs. In this video I cover just about everything you need to know about modern LiPo batteries and how to spec them for your project.

00:00 Intro
00:50 Different Battery Types
03:40 S Rating (Number of Cells)
04:46 Capacity
06:15 C Rating (Discharge)
07:43 Connector Types
10:06 Chargers
12:46 Charging a Battery
16:03 Safety Considerations
18:24 LiFe Batteries (Safer Alternative)
19:07 Advanced Discussion
20:22 Battery Fire!

[lucasanderson]

FINALLY someone who explains wtf the C rating is. That's the one thing I've never truly understood about Lipos.

[sprobertson]

This is possibly the most informative video I've seen on any topic. Also top notch delivery, you just breathe out knowledge.

[fabiangraz]

You told me everything I've been looking for for the past 5 hours thank you :3

[jrrobotics]

I have a feeling this is going to be useful in the future

[yuvrajghorpade]

Definitely need an advance battery video! Specially when one cell dies and how to get it back!!!! Please do it soon!

[DcMicroDiy]

covered all the basic's thank you..
made most of doubts go. . .
cheers

[SargentSkroonk]

Thank you for making your own version of battery video.

There is a lot of convoluted, contradicting, and incorrect battery videos, which yours is refreshingly NOT.

Yes. Please add an advanced battery tutorial, including how to jump an over discharged battery.

[laynegustafson]

Also very interested in an advanced battery video!!

[NewAgeDIY]

Excellent review, learned a lot, filled in a lot of missing information. I’m more interested in service robots like a self-driving vacuum or auto-sorting machine.

All of course using battery power. But you never know, one day a could build a battle-bot.

Thanks for sharing your knowledge, you are a great teacher!

[charlessampson]

This is a great primer. 2 bits of feedback:

Would have liked to see you talk about the importance of monitoring cell balance as part of the charging and safety sections (especially since you had the cell checker in hand already). Trying to charge packs with bad cells is a leading cause of LiPo fires.

Also worth pointing out that the manufacturers of hobby batteries like those shown in this video are notoriously dodgy when it comes to C rating and any published C ratings on those packs needs to be taken with a very large grain of salt.

[MegaNicmaster]

Great video! I'd love to see the same type of video about transmitters and receivers!

[michaelwoodworth]

know im late to the party but a custom battery video sounds awesome

[ShannanMcPeak]

Nice work. Great clear and concise vid. Nice being able to skip the clearly marked sections. Am very interested to know more about discharge issues, or more specifically, is it OK if LiPo/LiFe packs are overdischarged and what to if anything if they are. Cheers

[elitedogger]

This was super useful, thanks for making it! I find it interesting how my phone battery is around 5000 mAh, yet weighs probably under 100 grams. Of course the lipos can deliver their juice with much more power, but they clearly aren't efficient for mAh/weight :)

[EleanorPeterson]

Hmm... Interesting stuff. My early fighting robots were powered by 12V lead-acid car batteries! Then we tried vented gel-cells, which had the same chemistry but could survive being tipped and flipped without spraying sulphuric acid everywhere. (So... er, yay.)

For combat robots they were a pain because something like half of the weight allowance went on just the batteries. (We built 100-pound bots that could cost a maximum of £100.)

Ni-Cad technology seemed like an improvement - cells were much lighter - but things were horribly expensive by the time you'd welded a decent pack together.

Each cell needed so much care and attention it was like trying to keep a flock of suicidal tamagotchis alive. There were no 'smart' chargers, so maintaining Ni-Cads involved more cycling than the Tour de France, a lot of guessing and cursing, and was a real chore. Charging took 16 hours, and the batteries were still garbage.

Ni-MH cells are good. Still far too expensive, but they're tough, durable and flexible. I've got some very good ones ['Eneloop'] in my RC Tx and various bits of camera equipment.

I'm not impressed by Lithium technology. Yes, it's light and energy-dense, but it's too fragile, too temperamental, too demanding, and (surprise, surprise) far too expensive. The sophisticated charging and water cooling systems needed to make full-scale electric vehicles work are absurdly complicated and make current EVs (pun intended) little more than amusing toys for rich boys.

Prices need to drop by 85% before Lithium batteries become practical and useful; and even then, the limited number of charge/ discharge cycles is woefully low for the costs involved.

Gosh, I'm a grumpy cow, aren't I. So this Comment might as well end on a downer, too. The next phase of battery chemistry (cheap, robust, durable, cheap, flexible, cheap, cheap, cheap, etc) will arrive just in time to power the hearse EV that will convey my dead body to the recycling facility (a.k.a. crematorium/ Soylent Green factory) where a battery-powered furnace will turn my corpse into a greasy wisp of smoke.

Sigh.

[kfwoeltje]

Great video - would love to see an advanced tutorial.

[Rich-can-do]

ty that was wonderful I am using NiMA as I feel safer with it but this safe version of lipo sounds interesting too.

[rohanisousbois]

Very good video, thanks ! I'd be interested in some explanations about how to implement a battery inside a circuit, let's say I want to power a simple 12V LED strip but I want to charge it with a "standard" charger and I don't want to take out the battery (like any ready to use device actually). Anyway thanks angain.

[blackhawksp]

Hi. So I'm about to start my first ever attempt at this hobby and I just noticed that I ordered a battery with an xt30 connector (I made a couple of different orders and the battery arrived over two months later than the rest of the components so I completely forgot about the connectors), would it be safe to change cut the xt60 conector on the deans - xt60 adapter and then solder in an xt30 one?

[waynefilkins]

Some of the most complicated shit I have encountered in my projects is batteries and motors. So many ratings and just I feel like they have overcomplicated all this stuff. There's like amp hours and amps and volts and watt hours, watts, s rating, c rating, all kinds of max ratings, and like stuff can overheat...it's like holy sht man I can't build anything with a raspberry pi because there's all this shit and if you do 1 tiny thing wrong you burn out expensive parts or catch something on fire. I have this really badass project I want to make but it takes several motors and batteries and I need a specific torque and speed rating and I have no clue how many volts or amp hours or any of this shit man. Hoping this video helps lol.