I can't tell how many times I went back to this video. It's the best video about the subject I ever found on youtube after a few days of search. Thanks for posting it. :)
Fantastic demonstration and explanation! Thank you for sharing your knowledge in a user-friendly way! Applying this formula to my combat robot body now! ❤
Love your videos. I came across this video while working out in my head if I could use some of my smaller packs to get longer flight times in my Atomrc Dolphin. I now see that I can!
Thank you so much for making this video. I am very familiar with the series and parallell do's and don'ts on agm and lead batteries for car audio and electronics. I just wasnt sure about doing them with LiPo for my RC trucks. I was thinking that this is what was needed to be done to get 4S,6S or 8S with the lipo batteries that I have. I upgraded my rc trucks ESC, which is able to run with 3S up to 8S lipo batteies, I was looking on here to see what I could do to make my XMAXX rip with what I have for lipos on hand. Wow, I apologize for rambling on about everything here, all in all what I was trying to say was this video was much appreciated thanks again. 🙏👍
Very nice, this is the best and clearest explanation and demonstration anywhere! It was fun to watch even though I learned it 2 years ago, but wish this video had existed then.
Chris started asking questions and I thought, "If Chris is asking, other people may have the same questions" so we put a video together. I appreciate your feedback.
Thanks for helping make it. You asked good questions that anybody new to parallel and series connections would want to know. It helps me level set on the amount of detail I need to include in videos. I'll be curious to see how you apply this knowledge now ;)
Simply the best and clearest explanation and demonstration. Love all of your videos!! Thank you for sharing your expert advice and knowledge with all of us. You give us the confidence and knowledge to guide us safely in the hobby!! Gratefully, Sup Dog
Best explanation I’ve found on RU-vid 👍👍👍👍👍👍👍😁😁😁😁 When I got my 1st 6s rc car the hobby shop connected my negative from 1 to the the Positive on the other creating 1 battery I recently bought a new RC and got crap from the new hobby shop I use because I was connecting them directly rather than using the XT90 with the xtra wire running from the neg of 1 to the pos of other I then saw other videos saying that that xtra wire was just a waste of time as it’s just adding another connection to your power supply so I went back to the bullet connection system but as I have 200c discharge batteries I swapped to 6mm bullets from 3( maybe 4)mm to give the best power flow possible I’ve found that by switching back to my original system and using the bigger connectors that the power delivery is smoother, less jittery I hope I’m making sense here as I often find putting this stuff into words difficult! I would love to hear your thoughts on this if you have the time , if not thanks for making such an easy to understand video
Ty so very much. You really taught me something. Now I am thinking about manipulating battery wiring in order to get a desired result. Like using 4 smaller batteries to provide more power compared to a single battery of the same "capacity". I think I got it. So wiring in parallel would be best if you have two smaller batteries and you want to have more capacity as long as they are the same wattage. Series is if you have two larger batteries but want more power as long as they are the exact capacity. You will burn out the smaller battery otherwise. If you want both you would first take 4 batteries and have 2 sets both in series and then connect them in parallel. Following the rules of course. Then there is the motor capacity and shorter longevity. Ty again....When I was young if you were a trades teacher I would have taken those classes. Hell I am older and would now if you were teaching me.
"as long as they are the same wattage" I think you mean voltage. Yes, connect in parallel with the same voltage and you get more capacity. Parallel = Same voltage/more capacity. Series = Combined voltage/same capacity.
Man I love your vedios and perfect timing for me, so I'm flying my plane with a diy 4s 2p 6000mah 18650 pack I want to connect a 4s 1p 3000mah in parallel to now have 9000mah is this correct? The 4s 2p pack has c rating of 30amp the 4s 1p has c rating of 15amp so when connect in parallel what will be the c rating? I'm guessing 30amp?? Thanks for all your video's
Very helpful! Reminded me of undergraduate EE classes. Well done. U apparently have an opinion about parallel charging. Someday u need to tell me about it. So parallel makes u go further/longer and series makes u go faster/stronger.
Parallel charging gets religious for some people. In fact Battery discussions in general are largely anecdotal. The amount of magic, mystery, and conjecture in the RC hobby is astonishing to me, but when it comes to batteries, the level of [incorrect] subjectivity rises to mind blowing levels. That is why as a rule I try and use video evidence. When it comes to these controversial topics the answer must simply be "show me", don't talk about it, "show me". If I've done the homework, lived with a process, and know the outcome--as with parallel charging--from first hand experience, you're going to have to "show me" why I'm wrong because there are those who insist they know what they're talking about and persist in the dogmatic passing of bad information. I LOVE learning new stuff. What I don't like is people trying to pass flat wrong information along as gospel. Want to test this? Go ask 3 random people at the field what the "C" numbers on LiPo batteries mean, then go learn about it on your own. How close were they? How many said, "you know, I really don't know" Another one: Ask how to "trim" throttle on an electric plane [Hint: You don't, you calibrate the ESC]. This should give you a big clue as to why so many times in my videos I say, "let me just show you" and is the underlying reason for why this channel exists.
I just ran into this video 👍🏽👍🏽,I have a question, I have 3 4s lipos that I just want to run for more time on my max 5,do I hook one up to the max 5, then with the other 2 with a parallel spliter, then to the max5? For more gas in the tank,all the batteries are the same mah.thanks for any advice.
I'm subbing only cuz dudes a hot head 🤣 you can tell he's tired of people trying to argue with insufficient knowledge on the topic lol. Comments must be fun here 🤭
Thanks man, nice video ! Questions I have, is it possible to mix both up to one output ? Looking to power a large warbird with 14S/20 000 mAh, can I hook four 7s packs, two sets of 7s/10 000 mAh in \\ to get 20 mAh and then these, in series’ to reach 14s up to the ESC ? Is there any considerations to be taken or things to be aware of ? Thanks
Yup, you can. The considerations are that in series if one battery is soft (high IR/degraded capacity) and the other is in good condition, the soft battery can be killed while in series as there is only one path for current. So the stronger battery will keep going even if the softer battery is dying. This is true for any series connection, so my suggestion would be to make sure your packs are all in roughly the same condition by evaluating their mAh capacity and IR. Don't push too hard early on regarding your floor voltage. And measure/measure/measure while you dial up the flight time to make sure your batteries are all able to provide sufficient power to your combo.
Question: Let’s say you have two 4s 4000mAh Li-Ion packs with a max 45A current output, and you hook them up in parallel, this would give you 8000mAh, but would the max current output also double to 90A? Just trying for confirm, cheers!
@@RCVideoReviews ok, I was pretty sure that was the case, but wanted to confirm. That’s a pretty big benefit when using low discharge cells like Li-Ion, or low C LiPos. Thanks for the great video and info, cheers!
So it would be ok to connect 2 4 cell 2200mah together to get an 8 cell 2200mah 'pack', could I then do the same with another pair, to get 2 x 8cell 'packs' then connect them in parallel to get a 440mah 8cell pack?
Can we connect ** two different C rated 3s *battery in parallel (suppose one battery is 2200mah 50c another one 1000mah 40c ? I will use it in 12v spot welding which need 150amp .. Pls reply
You can connect different C-rated batteries together, but the circuit doesn't know anything about C ratings so if you load 150a you're going to get 75 from each cell. That is beyond the rating of your 1000mah 40c which is only 40a, so you will probably damage it.
I have a 7.4 V 850mAh and a 7.4 V 500mAh in both of them appear to be to sell. How should I connect them. This is for a 1/18 scale RC truck that I built.
It depends on what you're trying to do. If you want to increase capacity, you connect them in parallel. If you want to increase voltage you connect them in series. Since these packs are different sizes (850mah vs 500mah) you should not connect them in series because the smaller battery will be drained faster than the larger battery which will damage it. So the only thing you can do in this case is connect them in parallel. I covered these rules in the video.
If I added a second battery and connected it in parallel should my current charger charge them equally and would I need to match their level before connected or should my charger do everything?
Never connect two batteries in parallel without ensuring cell to cell voltage is close. I aim for within 0.02v That said, if you DO connect batteries in parallel, the one with higher voltage will try to charge the one with lower voltage until they reach equilibrium.
Alright what I don't get is... Let's say we have 2 cell/batteries whatever, that we need to connect in series. Both have the same volt but different mAh (1000 mAh and 1200 mAh) which should be a big no no as you mentioned. But what I was wondering was, wouldn't the 1.2Ah cell just start charging the 1Ah cell when the 1Ah cell runs dry? I thought that's how it worked. ________________________________________________________________________ Can you please tell me if I can use my 2S 3000 mAh lipo and connect it with my 1S 1000 mAh in series to get a 3S lipo if I only fly for a minute of PID testing without crossing the threshold of 900mAh. Always using my lowest capacity battery as the benchmark and never going over its limit?
If there is no load yes, the higher voltage cell would charge the lower voltage cell, but under load, the current will flow from both damaging the lower voltage cell. Remember, you can only go to 3.3v before causing permanent damage. You can connect a 2s 3000 to a 1s 1000 as long as the 1s 1000 doesn't go below 3.3v.
Hey John when you connect the two individual batteries packs in series do you parallel charge them first and does that balance charge them to each other or can you also just balance charge the 2 individual packs and connect them. Im pretty sure either way is okay just want to check with you first. Cheers
Can I assume when you say BMS that you're referring to a charge circuit that balance charges your batteries? If the answer to that question is "yes", then my answer is I would not do that. When you start putting batteries in series, you need to balance charge them.
Hello mate, I just by mistake connected esc with lipo in wrong connection now my battery 1 cell is to 0 volts I was using 3 cell luckily my esc is still fine can you please suggest what shd i do
You probably burned or shorted a balance lead or a series connector between cells. Since you're asking me this question, I'm going to assume you do not have advanced electrical troubleshooting skills. Therefore, you should probably dispose of the battery.
I want to use a series parallel configuration to run my minkota trolling motor on my kayak with 12 2 S 7.4 5200mah Batts 2 Batts in series for 14.8 volts then Parrelell on every pair of 6 that have been series conected any issues? I am currently using a group 24 marine deep cycle 12 volt batterie let's just say either I have to lose 20 lbs or the batterie does .I'm still liking my food
How will you balance all of that? There's nothing electrically wrong with what you're suggesting. You're basically making 6 4s packs and connecting them in parallel. Here's what I would check if I were you: 1) Make sure IR is close on all packs. 2) Keep them balanced. 3) Close in their cycle count. 4) Same discharge C rating.
@@RCVideoReviews thank for the feedback my thought was to have each lipo pack on a pre wired board with plug connectors so I could pull each pack and balance charge individually then replace modules when and where I need . Half my battery are 50c and the other is 80c is that going to be trouble?
@@jonandkariwalter2074 You'll find that higher C packs will hold their voltage under load more evenly than lower C packs. I've never really considered what that would be in practice for Series or Parallel, but I would expect to see some disparity like at the end of the day your lower C packs drain faster than your higher C packs so you wind up not getting the full charge capacity before hitting a cutoff voltage. --Again just spitballing here, but my preference would be to use packs with the same C rating on discharge. As long as you have a strategy to balance charge, you're good there.
@@RCVideoReviews ok thanks. because i have curmudgeons telling me the resistance will be so high that i should just use 12s... not sure how that makes sense, but ok. they keep saying "i have lots of experience! just listen to me!"
They're wrong. If you connect your devices in series properly it's no different than using a 12s pack. Just nonsense. My 85" planes and 700 helis all use 2x6s. See the numerous videos on my channel showing those craft in flight.
Thanks for the video, though I was always taught never to put these in parallel without a diode in series with each output. To prevent one battery charging the other battery. Or if one battery dies, it wouldn’t affect the other battery. But fair enough, if they have both the same voltage it’s ok. I’d use two diodes though … Schottky type with low voltage drop and current rating exceeding the maximum expected. Cheers.
I've been charging and discharging batteries in parallel for years. I have planes that use parallel batteries in flight. Higher voltage means more motive force, so it seeks out lower voltage and current will travel to it. This is why we keep the voltage within a few 100th's of a volt for parallel connections. That only really matters when the balance leads are connected. When the mains are connected, the error can be a little larger. In any case, a diode just isn't necessary if the voltage is close. But, you're money, your hobby, do whatever makes you happy.
Hi, do I need to be careful with different discharge rates and / or internal resistance when combining in series and parallel? Im guessing this is why you are using the same brand of battery as they’re the same specs? Thanks, much appreciated.
They do not have to be identical. The farther apart IR the less effective capacity. The batteries will always follow ohms law so they discharge to load which is why in parallel they will discharge evenly. Off load you will see the lower IR pack end with higher voltage than the higher IR pack. In my experience, once packs start to get puffy (flex on the sides when squeezed), the IR is higher than new packs. Once IR hits about 5 as measured by my iCharger 306b, I stop flying the pack. So when I fly with packs in parallel or series, you are correct - I try to keep similarly spec'd packs working together. i.e. I try to keep packs with average IR of 1 together and packs with average IR of 3 together.
RC Video Reviews thanks for the info, really helpful. I don’t have any instruments to measure IR so I’ll just try get batteries with similar IR when I buy them. Is there any disadvantage to building a 3+ parallel battery group, when compared to just buying one battery of the required capacity? It is sometimes cheaper to buy batteries that way, although it seems unintuitive. Thanks again
@Eiren Whelan I believe all new LiPos come with an IR of 1. What happens after you start using them is a function of heat/discharge rates/discharge voltage/cycles and any number of other factors. I frequently look for series or parallel options with smaller packs to give me larger packs if it helps me avoid buying single use larger packs. The only exception I've made to that in recent years is for my BAe Hawk. For that jet, I sprung for some 6s5000 batteries.
@@RCVideoReviews I bought an UAV plane. Now I just learned from you that I can increase the range by adding an additional battery and make it parallel to the existing one. " more gasoline in the tank "
@@franciscourena5636 You got it. Parallel is more gas in the tank. Just watch your weight. Adding batteries is normally not a 1:1 proposition. i.e. Double battery doesn't mean double flight time because your plane is now carrying more weight.
In your Serial and Parallel examples you haven't mentioned cell balance. Perhaps it's obvious to those more experienced but must all batteries (as 'usual' for lipo) have their cells in balance?
Anytime batteries are used in parallel they should be in balance because they'll all be drawn from in parallel. It's less critical in series because the voltage is additive; however, in series one cell can be drained before others if its capacity (MAH) is lower. So for that reason, it's also smart to start with cells in balance for series connections as well. General rules are: Parallel - Same voltage, different MAH ok. MAH is additive. Series - Same MAH, different voltage ok. Voltage is additive.
@@RCVideoReviews oh, serial is perfectly fine for me! It's just that at some point in the video I heard it as 'cereal' in my brain and it made me laugh! :p Thought I'd share, in the hopes of making someone else chuckle! ^^
Can I have 2 batteries In series both 36v 10ah and then take another 36v 20 ah battery and run that parallel then it will be 72 v 30 ah battery is that correct?
"Can I have 2 batteries In series both 36v 10ah" 2 batteries in series that are both 36v means you will have a 72v battery. "and then take another 36v 20 ah battery and run that parallel" Absolutely do not do this. You'll wind up with sparks and fire because what you just said you want is to connect a 36v cell to a 72v cell in parallel. You do not mismatch voltage in parallel. You have three batteries all 36v. You can connect them all in parallel and the load will drain all three evenly. DO NOT put two 36v cells in series and then connect a third 36v in parallel.
@@RCVideoReviews I think I mismatched the words Parellel and series. I got 2 36 v 10 ah batteries I connected so it’s 72 v 10 ah if I bought another 36 v 20 ah battery and connected now to positive to positive and negative to negative to will it become a 72 volt 30 ah I really appreciate your info
No. STOP! DO NOT CONNECT a 72v battery in parallel to a 36v battery. You really need to study this more. PARALLEL = + to + and - to -. VOLTAGE should be the same. SERIES = + to -. VOLTAGE IS ADDITIVE Absolutely do not connect a 36v cell to a 72v cell in parallel.
Incorrect. Current is the result of load. Connecting cells in parallel does not change load but it does combine the capacity of the cells connected and ALLOWS more current delivery capacity. Merely connecting cells in parallel does not change the current. Current draw depends on the load, not the source.
Why would parallel charging cause problems ? I can tell you for fact it works and it's safe . My question is : I have a 1/10 scale RC truck and I accidently ordered the wrong 3s battery packs . They are for a 1/18 scale or airplane ....right voltage wrong size . Running a pack that small would over heat the battery cells so I wanted to run both 3s packs parallel . Can I do that ?
Parallel charging is great. I do it all the time, and I argue against people who come here and say it's unsafe. It can cause problems if you connect packs of dissimilar voltages together. Here's how I decide if I run packs in parallel: 1) Same voltage 2) Similar IR Cell to Cell and Pack to Pack 3) Same discharge C rating If those conditions are met, I will charge and discharge them in parallel any day of the week.
Series. I been trying alot but one battery gets life sucked out faster. Loosing to many new bats. My long reach plane came back with a lipo at 2.77 volts, other was 3.85 ( If some one comes up with a balancing circuit to install between them they get rich !
Heli guys fly with series all the time. Do you keep matched pairs? Same manufacturer, same age, same model etc..? Seems like maybe an IR problem or resistance introduced in your series connection?
In parallel, IR is cumulative. So if you have a pack with high IR it will 'drag down' the performance of a pack in better condition. Personally, I try to keep packs in similar stages of performance together.
@@RCVideoReviews Oh yeah, sure.😀 I just wondered if anyone made an adapter for this. One that goes in the right direction. 1Male to 2 Female. EC3, Xt60........ I don't recall seeing one anywhere.
@@airhammer6203 That I don't know. Wouldn't be hard to make though. Amazon sells XT60 connectors pretty cheaply if you want to make one. I make my own parallel connectors.
