it is used to describe the discharge ability, as if a 10000mAh batterty, 0.5 C(Capacity) mean the discharge current 0.5 x10000=5000mA, 1C mean the discharge rate 1x 10000=10000mAh, 2C mean 2 x 10000 = 20000mA. Price 2C > 1C > 0.5C
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.
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.
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!
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.
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 :)
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
NiMA? What's that? If you're not using some form of lithium battery in combat robots, you're gonna have a bad time. You need that energy density and power delivery. Definitely look at LiFe.
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.
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.
those are two different things. when you say '9v battery' do you mean an actual 9V battery? those have almost NO current delivery, usually only 200mA or so, which is a fraction of what the ESC would need.
It depends on the charge. If they are fully charged the internal resistance will get bigger over time so the lipo gets worse but it’s not really dangerous. If they are to low for a long time (under around 3,4v) they can get puffy and then it’s dangerous to use them again. Puffy lipos are a bad sign in general. If you store them at 3,8v they will probably last a year before you need to charge them again.
So if I have a 24v 200w scooter motor, can I expect a 22v 10,000mah Lipo battery to last around an hour? .... 200/24 = ~8A, 10 / 8 = 1.2, rounding the 1.2 to 1 hour to allow for other variables.
The motor consumption changes a lot so your calculation does not really work in reality. For a scooter the motor will need more than 200w or it will be a very slow ride. For vehicle efficiency / range it’s best to measure average Wh/km and then you can use the battery Wh to judge the range. A light and efficient scooter will use around 7wh/km and a faster high power one 15-20wh/km Your 10Ah 22v battery has 220Wh so it will probably go at least 20km and up to 30-35km if you are slow and/or assist it a bit with pushing. You can’t really calculate run time unless you drive on a flat road without ever breaking or accelerating for the whole battery. Every start, stop, hill, wind ... will significantly impact the power consumption.
@@blise518B Thanks for the reply. My mistake, it's 250W, not 200W. I'm not actually using it as scooter motor, but instead to power the blade of a remote controlled lawn mower. The motor is advertised as 24v 250W (14A rated current). So I assume that means 14A under load? so 330W under load, and 250W without load?
@Ben Jamin Awww crap the good old motor data. First of all the data is what the motor is designed for. In most cases you can go outside of this range by quite a lot as long as you check the temperature. How much it will actually pull depends on your motor controller. In some controllers you can set the exact current you want in others you simply need to experiment with the pwm signal to get the power you want.
Those are Li-Ion batteries (generally) and they are OK, but it's much better to get a LiPo pack that meets your requirements. The voltage on your phone will be too low, and it won't have a high discharge rate.
would it be safe to take the two LiFe battery output connectors and solder a new one on that combines both output leads? not confident a single connector could handle the current demands required for what I'm making even though the battery claims it can
This could work. I would worry that you'd be limited to the size of the wiring though. The connectors can usually handle quite a bit of current. But connecting two batteries in parallel would work in certain cases. You can always add new connectors and use a Y splitter as well.
@@RobertCowanDIY Yeah, what I mean is soldering both positive output leads to the same positive output of the connector, and same for the negative leads. The single set of output wires has me concerned for current output, and I need the full discharge from them. The overall plan here is to run two 3Ah 20C 2s LiFe batteries in series for the weapon I'm making. 15lb class, so LiPo is banned. Sucks, but it is what it is
@@happyfaic72 TECHNICALLY this would work, but it's a bad idea. What if one battery has an issue, it would take out both. You would want to go into a splitter instead. Charging would also be tricky. Just use two of them and make your own wiring harness. It makes it easier to remove and replace batteries.
@@RobertCowanDIY Yeah, I also intended to do that lol. I just want each (separate 2s) battery to have a single output connector instead of two smaller output connectors, so I can make a more effective splitter to finally wire them in series. I think it's dumb that these batteries exist with two output connectors in the first place, but I guess that's what you get when they're called receiver packs since I guess they're at the right voltage to just straight up plug into receivers to power them.
Do you know the difference between "Series" and "Parallel? Not trying to be a smart ass but, you and Robert Cowan are using different terminology here. You keep saying series and he keeps saying Parallel. In a series application, which is red from one battery to black on the next battery, you would only increase the Voltage and not the amperage. In a Parallel application, you increase amperage, but voltage remains the same. ie. 2 12v 20A batteries in series would be 24v, 20 amp. Conversely, 2 12v 20A batteries in parallel would be 12v, approx 40 amp, in theory. So, soldering the 2 red wires (Pos) together onto one pin of a connector is making them Parallel. Of course, the same with the black wires (Neg). FYI, More amperage causes more heat caused by the resistance of the wire and circuit, of course. So be careful about what gage wire you use. Rule of thumb, the larger the gage, the less resistance to current flow. This means that because the diameter is larger, it can handle more amperage and dissipate heat better. Also, a solid conductor wire will carry a little more amperage than a stranded wire of the same gage. The only drawback to solid conductor wires is they are stiff and have a tendency to break if bent back and forth too much. They will break a lot faster than stranded wire. Also, stranded wire can melt easier than a solid conductor wire. I sure hope I haven't confused you too much.
I thought I did. It's basically the time component for power used. If you use 40 watts for an hour, you've used 40Wh. If you use 40 watts for 5 minutes, it's (5/60)*40 = 3.33Wh. Watt hours are more like an 'amount' of used power, where as watts is an instantaneous value.
I bought one fake charger and it died within day. the last battery it charge was 6s LiPo (with very low current) so i assume it just cannot handle high voltage charging.
I most likely have a 'fake' one. I got it from Amazon and it's been a champ. I have two of them and they both work flawlessly years later. I think if you spend a reasonable amount, it should be fine. Generally $50 is as low as I'd go for a decent charger. Any less and it might be garbage.
Most of time the counterfeit will work just fine, as suggested by many other users online. My main concern is safety and quality control that they put into effort. I opened up the broken charger and found out the power supply in the fake IMAX B6AC weighed almost nothing and doubt it can deliver the enough current for charging. I may had gotten the worst fake out there and hope others know this and pay a little attention when buying their charger. I switched to ToolkitRC M8 and it's great bargain for price and performance.
FINALLY someone who explains wtf the C rating is. That's the one thing I've never truly understood about Lipos.
it is used to describe the discharge ability, as if a 10000mAh batterty, 0.5 C(Capacity) mean the discharge current 0.5 x10000=5000mA, 1C mean the discharge rate 1x 10000=10000mAh, 2C mean 2 x 10000 = 20000mA. Price 2C > 1C > 0.5C
very interested in advanced battery!
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.
I have a feeling this is going to be useful in the future
This is possibly the most informative video I've seen on any topic. Also top notch delivery, you just breathe out knowledge.
You told me everything I've been looking for for the past 5 hours thank you :3
Definitely need an advance battery video! Specially when one cell dies and how to get it back!!!! Please do it soon!
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.
know im late to the party but a custom battery video sounds awesome
Noted. I've avoided making it for liability reasons, you need to solder to bare battery terminals, which can be a BIT sketchy.
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!
Yes interested in advance batteries
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.
LOL. The fact that you're not impressed with lithium batteries boggles my mind.
Also very interested in an advanced battery video!!
Great video thanks!
covered all the basic's thank you..
made most of doubts go. . .
cheers
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 :)
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
Exactly what I needed, thank you!
ty that was wonderful I am using NiMA as I feel safer with it but this safe version of lipo sounds interesting too.
NiMA? What's that? If you're not using some form of lithium battery in combat robots, you're gonna have a bad time. You need that energy density and power delivery. Definitely look at LiFe.
Great video! I'd love to see the same type of video about transmitters and receivers!
I'm a lefty and my radio has a strange configuration, so I might confuse people more than help them. But I've been thinking about it.
@@RobertCowanDIY lefty gang!
Great video - would love to see an advanced tutorial.
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.
It should, that's why I made it! You're the intended audience.
really tough. Your condition is more pathetic than me🤣🤣🤣
My fledgling robot thanks you.
Good luck!
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.
dont forget super capacitors, they are pretty amazing.
Advanced please!
Is it possible to use a 9V battery to a 30A esc?
those are two different things. when you say '9v battery' do you mean an actual 9V battery? those have almost NO current delivery, usually only 200mA or so, which is a fraction of what the ESC would need.
Can I charge a 7.4 v 950 mAh lipo battery on 1 Amp, or will it be too picky?
Yes, you can technically charge up to around 5S, but you just shorten the life of the battery. But right around 1S is just fine.
You didn’t cover over/under voltage?
Not in this video. That would be reserved for the 'advanced' video.
Can a lipo become unsafe from not being left at storage charge?
It depends on the charge. If they are fully charged the internal resistance will get bigger over time so the lipo gets worse but it’s not really dangerous. If they are to low for a long time (under around 3,4v) they can get puffy and then it’s dangerous to use them again. Puffy lipos are a bad sign in general. If you store them at 3,8v they will probably last a year before you need to charge them again.
I thought you should charge at half the C, I guess I'll be able to charge at double the speed now:)
1/2C is fine, it just takes a lot longer. But generally speaking, 1C will never cause you problems and is safe for all batteries.
So if I have a 24v 200w scooter motor, can I expect a 22v 10,000mah Lipo battery to last around an hour? .... 200/24 = ~8A, 10 / 8 = 1.2, rounding the 1.2 to 1 hour to allow for other variables.
The motor consumption changes a lot so your calculation does not really work in reality. For a scooter the motor will need more than 200w or it will be a very slow ride. For vehicle efficiency / range it’s best to measure average Wh/km and then you can use the battery Wh to judge the range. A light and efficient scooter will use around 7wh/km and a faster high power one 15-20wh/km
Your 10Ah 22v battery has 220Wh so it will probably go at least 20km and up to 30-35km if you are slow and/or assist it a bit with pushing.
You can’t really calculate run time unless you drive on a flat road without ever breaking or accelerating for the whole battery. Every start, stop, hill, wind ... will significantly impact the power consumption.
@@blise518B Thanks for the reply. My mistake, it's 250W, not 200W. I'm not actually using it as scooter motor, but instead to power the blade of a remote controlled lawn mower. The motor is advertised as 24v 250W (14A rated current). So I assume that means 14A under load? so 330W under load, and 250W without load?
@Ben Jamin Awww crap the good old motor data. First of all the data is what the motor is designed for. In most cases you can go outside of this range by quite a lot as long as you check the temperature. How much it will actually pull depends on your motor controller. In some controllers you can set the exact current you want in others you simply need to experiment with the pwm signal to get the power you want.
Can I use my keypad phone battery for combat robot
Those are Li-Ion batteries (generally) and they are OK, but it's much better to get a LiPo pack that meets your requirements. The voltage on your phone will be too low, and it won't have a high discharge rate.
It's 3.7volt
@@kalpanaverma4277 Yep, that's going to be too low. You could use several in series for higher voltage, but that voltage is too low.
would it be safe to take the two LiFe battery output connectors and solder a new one on that combines both output leads? not confident a single connector could handle the current demands required for what I'm making even though the battery claims it can
This could work. I would worry that you'd be limited to the size of the wiring though. The connectors can usually handle quite a bit of current. But connecting two batteries in parallel would work in certain cases. You can always add new connectors and use a Y splitter as well.
@@RobertCowanDIY Yeah, what I mean is soldering both positive output leads to the same positive output of the connector, and same for the negative leads. The single set of output wires has me concerned for current output, and I need the full discharge from them. The overall plan here is to run two 3Ah 20C 2s LiFe batteries in series for the weapon I'm making. 15lb class, so LiPo is banned. Sucks, but it is what it is
@@happyfaic72 TECHNICALLY this would work, but it's a bad idea. What if one battery has an issue, it would take out both. You would want to go into a splitter instead. Charging would also be tricky. Just use two of them and make your own wiring harness. It makes it easier to remove and replace batteries.
@@RobertCowanDIY Yeah, I also intended to do that lol. I just want each (separate 2s) battery to have a single output connector instead of two smaller output connectors, so I can make a more effective splitter to finally wire them in series. I think it's dumb that these batteries exist with two output connectors in the first place, but I guess that's what you get when they're called receiver packs since I guess they're at the right voltage to just straight up plug into receivers to power them.
Do you know the difference between "Series" and "Parallel? Not trying to be a smart ass but, you and Robert Cowan are using different terminology here. You keep saying series and he keeps saying Parallel. In a series application, which is red from one battery to black on the next battery, you would only increase the Voltage and not the amperage. In a Parallel application, you increase amperage, but voltage remains the same. ie. 2 12v 20A batteries in series would be 24v, 20 amp. Conversely, 2 12v 20A batteries in parallel would be 12v, approx 40 amp, in theory. So, soldering the 2 red wires (Pos) together onto one pin of a connector is making them Parallel. Of course, the same with the black wires (Neg). FYI, More amperage causes more heat caused by the resistance of the wire and circuit, of course. So be careful about what gage wire you use. Rule of thumb, the larger the gage, the less resistance to current flow. This means that because the diameter is larger, it can handle more amperage and dissipate heat better. Also, a solid conductor wire will carry a little more amperage than a stranded wire of the same gage. The only drawback to solid conductor wires is they are stiff and have a tendency to break if bent back and forth too much. They will break a lot faster than stranded wire. Also, stranded wire can melt easier than a solid conductor wire.
I sure hope I haven't confused you too much.
you forgot to explain watt hours
I thought I did. It's basically the time component for power used. If you use 40 watts for an hour, you've used 40Wh. If you use 40 watts for 5 minutes, it's (5/60)*40 = 3.33Wh. Watt hours are more like an 'amount' of used power, where as watts is an instantaneous value.
Batteries are more complicated than I realized. Haha
there's bunch of fake SkyRC charger out there and they are not reliable. main differences between real and fake are the box and price.
I bought one fake charger and it died within day. the last battery it charge was 6s LiPo (with very low current) so i assume it just cannot handle high voltage charging.
I most likely have a 'fake' one. I got it from Amazon and it's been a champ. I have two of them and they both work flawlessly years later. I think if you spend a reasonable amount, it should be fine. Generally $50 is as low as I'd go for a decent charger. Any less and it might be garbage.
Most of time the counterfeit will work just fine, as suggested by many other users online. My main concern is safety and quality control that they put into effort. I opened up the broken charger and found out the power supply in the fake IMAX B6AC weighed almost nothing and doubt it can deliver the enough current for charging. I may had gotten the worst fake out there and hope others know this and pay a little attention when buying their charger. I switched to ToolkitRC M8 and it's great bargain for price and performance.
🔋🤖🔋🤖🔋🔋🤖🤖🔋
Ingat.... Ada allah....