Calculating Battery Bank Capacity
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- čas přidán 5. 05. 2019
- This video explains how to calculate the energy storage of a battery bank based on the voltage and capacity of the individual cells.
In this video I used suitably sized neodymium magnets as a temporary way to connect cells together: ebay.to/2J3BoFG
❗️These links are affiliated and I may earn a small commission if you purchase❗️
#lithium #leadacid #alkaline #capacity #series #parallel
Noice! a very basic and easily understood video about series parallel circuits.
Short, sharp and concise.
Thanks Adam!
That was pretty explicitly explained. Nice job Mr.Welch.
This was exactly the video I needed to see, to learn what I was wondering about - thank you!
Always love your language, even though I am not native English! This is why I love your videos! Thumbs up!
Very well explained and nice demonstration of examples. Thank you!
so clever and simple ,you answered all my questions,you are great bro ,thanks
Just what I needed. I was so confused. Thank you Sir!
Thanks, Adam, that was the best explanation I have seen to date cheers
Good video Adam, be great to hear a comparison of available energy between the two battery chemisteries.
Very well clarified and explained
Nice educational video. Like a video classroom study. Thank you Adam.
Thank you Adam. Well explained and yes, it helps.
Glad it does. Thanks!
Magnificent! Thanks a ton!
Adam great video you nailed it
Yay someone mentions all of the battery / cell parameters correctly. Good job Adam. Love ur vidz
I tried my best! Cheers.
He did well, but he got wh wrong
Thanks for the explanation I was confused on wh and ah
HI ADAM THANK YOU FOR AN EXCELLENT EXPLANATION VIDEO
Very nicely explained ,,thank you
Good and succinct explanation - well done
Thanks Colin.
thank you for this video ❤️
I liked your explanation. and also have Q: how can I calculate the percentage of discharge or usable current?
Very nice explanation.
This helped me understand. What is the average usage you use in your shed?
Nicely explained
Thank you very much sir.
But even though I fitted the desulfator kit as recommended a year or two back, and its still blinking, my car battery packs capacity has not remained constant. 😀 I have however found an alternative solution to the problem of inadequate capacity. A quick trip to the breakers yard and adding a couple more on top of the stack.😀
Nicely explained 😊😊
Very good 👍
nice and easy helped alot thnx
Thank you so much
Nice bro. Now i know. Thanks
This was puzzling me, I really would like to get into this, maybe just so I’ve got some battery power I could take camping. I’m no stranger to electric, and harvesting cells appeals to me but I’ve got no idea where to look, any suggestions?
thank you so much
Nice video. Very clear explanations! Now I'd like to know how much Watthours you need to put in to get these packs fully charged, as well as how many Watthours you then can get out off them, for instance to power the equipment in your shed. Any thoughts on that?
Thanks. It’s a chemical reaction which has losses. Heat is created both when charging and discharging - so you’ll always have to put more in than you get out. The real capacity is somewhere in between these two numbers.
@@AdamWelchUK - I understand. I kind of was wondering which technology is most effective. If you harvest 5000 KWh with your solar panels, what is then the best storage at the moment? Which pack would give your most working time on your laptop? Is it your Li-ION set or the Lead-acid pack? Where do you find lowest losses in charging/discharging and in battery management?
Pls I want to ask..
I'd like to make a power bank of like 15,000mah with 6batteries..how do I go about the connection??
Just great
Coming up next, measuring the reality and facts of energy losses in chargers, buck/boost converters and inverters. :-)
You cannot calculate watt hours. You can only measure it. This is because the voltage decreases as the SOC falls, so at any voltage below nominal, the watts are not as high as calculated when using nominal
so if i have a 20v light that draws about 1 amp and runs on 12v , and i want it to last say 6 hours , will 9 18650 ( 2000mah) work . I think i wire 3 groups in series of 2 parallel ?
Have you made a video on how to make a 100Ah battery pack form 18650 batteries?
How many would it take to replace your car battery ?
Tha is bro so helpful . So for example my e scooter m365 I think it’s a 4 or 5 a
Thanx for the video brother...correct me if Im wrong......according to the data sheet the Maximum Continuous Discharging Current is 4400Ma or 2C...for each cell....therefore I have 10 cells in parallel and the total Maximum Continuous Discharging Current then it would be 44000Ma or 44A for my lithium ion battery.. my battery is 13S10P 52V 25Ah...
Dearest Adam.......Please Please can you show me how to change your old Arduino Capacity meter code using 5110 screen to do Resistance only checking for 18650 ? loading cell up with say 1.5 Ohm resistor for 10 seconds only with latching push button....
I always wanted to know AH of my 18650 battery 13S 5P, so it's 48V 10 AH
if you are running it in parallel do i have to used a bms
Sir, that means the total amps of 12.6v ,or that nine batteries gives 6 amps..? or is it 18amps.
I have ten 3000mah 18650 batteries in series (36v) and ten in parallel (10S10P(?) Is the total energy stored in my pack 1080wh???
If I want to increase a 14.4v - 3.8Ah battery pack (4x18650 3.7v Lithium Batteries in series) to gain more Ah, can I add a fifth battery in Parallel to give me 14.4v with greater than 6 Ah? and will I have an issue recharging it with 4 batts. in series and 1in parallel?
For you to get more Ah at 14.4v, you have to connect another bank that's of 14.4V to the existing one. This implies that you have to make another 4S lithium battery and connect it in parallel to the existing one you have. For instance, you have 14.8v 2.2Ah (4S or 4×18650 3.7v 2200mAh Lithium battery in series) and you wants to increase the rating to 4.4Ah or more, you have to make similar of the existing one and then connect it in parallel.
I calculate my capacity using an arduino. I take a reading every minute. I use a cutoff of 3.2 volts and the arduino stores the current and voltage and a counter keeps track of the number of minutes. When done, the arduino calculates average current and voltage then multiples that by the time (converted to hrs). Thats how I get my capacities.
Sounds very similar to my basic arduino battery capacity project a few years ago. Great to build a solution all by yourself isn’t it? :-)
Joey you are doing it wrong. You cannot average the voltage because it is not linear. You must sum all the individual watt hours or it will not be accurate
@@climatechangepreppersfaceb2148 Its pretty linear between measurments.
I'm trying to figure the math on peak amps delivered when I flick a switch. That switch would only be on for ~1 second. 6 AAs provide more than a single 9v or even two 9vs in parallel. The equations I know of make sense, but I must be missing or misunderstanding something because I think 2 9vs ought to be significantly better than 1 9v, but it's not, and the AAs outperform the 2 9vs. I don't have the right language to find my answers as of this morning.
Why do you have all those battery banks, what are they for?
Are you up for answering any question on my 48volt forklift battery bank run on a outback flex one system
john goulsbra - Exactly.
You can try me - although I don’t use outback kit.
I've several times toyed with the idea of putting together packs of LIon batteries to replace my 35AH SLA batteries in my solar system.
So if you have three batteries, all tested at 2000 mA hours and put them in parallel that is a 6000 mA hour pack?
Where does it say on the battery what the ah rating is?
Hey Adam, even though I know this it still sucks you can't use the capacity from each in series. I've had some crazy questions like why do you need to fully charge all cells after the first bank and why can't you only use 1 cell just for for the voltage and on and on. It's such a simple thing to parrot the way things are done and another whole matter of what and why and getting some people to grasp the underlying functions when these people will never use the knowledge anyway, but looking to squeeze every last bit and most of them will tell you there's a way, but you're not aware of it yet. lol I made people watch me charge a 5s pack all spot welded, but charged individually to 4.2v to get a total of 21v and the fact they wont self balance unless it's 10 or whatever number in parallel. People are baffled and I can understand where they're coming from. Good to hear from you.
If only we could double the capacity when we place cells in series. That’d be some sweet free energy! Good to hear from you MrB
1. The ratio of current to time is not linear.
2. Everyone should label their batteries in Wh ...
3. I see that you have fuses on all parallel connected batteries, good.
In the video he showed that if he connect in paralel the amps will increase but then how the the voltage increase from 3.7 to 4.2 volts
How are your lithium cells kept in balance if the packs are 20p? Does the circuitry balance each cell individually??
I believe all cells that are paralleled together automatically balance out to each other, thats why they need to be all equal when its first built. and then the series packs are balanced controlled..
Cells in parallel will balance between themselves because they all have a common connection. My groups of 20 use the diyBMS to balance the voltage between each group. I’ve a series of videos on the diyBMS. It works great.
I have made a 36v battery with 10 group every group 3 lithium battery total 36v thats mean every group gives me 6 amp and total 60 amp??
Hello I am trying to design a Laptop power bank with Lithum 18650 batteries
The Specification of the system charger is
Input AC 100~240 ,1.5A
Output DC 19.5v ,4.62A
What is my best approach to building this power bank
Good old ohm's law. Have a wonderful day.
Good illustration Adam.
We should try to get more people thinking in terms of Wh and kWh, as they easily add up whatever the configuration.
Also irritates me when people mix up kW and kWh: flow rate and volume are not the same thing!
Thanks Andy. Hopefully a few people new to this subject will stumble across this video and it’ll help them.
Andy ..... volume in kWh?. ...... and you thought you were irritated :))
@@whitefields5595 Think of water pipes and tanks, then volume makes sense.
A battery is a box of joules. It has volume.
Power is a flow rate, where 1W = 1 joule per second.
1kWh is 3,600,000 joules.
Bricks per second -> pile of bricks etc.
Same thing with electrons or ions or energy states - they have a volumetric dimension too. So a higher charge potential has a greater density of charge carriers per unit volume.
Current = rate of flow of electrons.
Charge = quantity of electrons or ions, and they occupy a volume (capacity).
Energy density = how tightly packed they are.
Power density = how quickly energy can go in or out per unit volume (eg, supercapacitors have high power density but low energy density)
@@ahaveland A battery is not a box of Joules represented by volume. Volume cannot be related to energy, or the capacity (cf ability) to do work (power). You cannot apply the dimensions of volume to either energy or power. The nearest you can get is to state 'the capacity to do work' .... but you didn't. (If you did say capacity then someone would ask about capacitance!)
Electrons are stored on flat surfaces so an area analogy may work, but that is not the context in which you introduced volume.
You cannot have "power density" either ... only power. Even energy density is stretching it but has slipped into common parlance. It is really energy per unit area (of the electrodes)
Supercaps have lower stored energy but very low internal resistance hence higher current which depletes the energy (Wh) quickly. Nothing to do with your term "power density", just high current giving relatively high power but for a short time compared to a battery
Far easier to use the correct terminology. It is eventually easier for all to understand, or go away and find out.
@@whitefields5595 Many people do not understand though, hence the point of the video.
As a conceptual model of scalar quantities, a watt is a thing per second, and a watthour is the number of those things over time.
It is *exactly* conceptually equivalent to litres per second vs litres and can be represented by pipes and tanks.
You also misquote what I said.
Batteries are boxes of joules that *have* volume, not "represented by volume".
Yes, power density is a thing.
You do not know it all. Use whatever you think works for you.
What I don't understand is why Ah is used at all. There is no reason at all to use Ah instead of Wh, is there? It basically uses a value that requires complex measurement or integration of the voltage to be usable.
Is it done as a marketing trick to be able to more easily confuse and manipulate buyers? Or just bad tradition?
Because most videos that talk about "energy" talk about "amp hours" or "amps used"
Hello!
I need diagrams apparently, I'm getting throwed off when people start soldering the connections, I'd better make my own...I hate electronics
So, your 7S have 50Ah? The 140 pcs of 18650cell will give you only 50Ah..
Yeah, each block is 50Ah at 4.2 volts but the whole pack is 50Ah at 29.4volts - or 1470 watt hours, 1.47kWh.
@@AdamWelchUK I am in middle of testing and charging my cell, the plan is to make 7s 80p if I get good cells. if now, it will go down to 70p. I will keep all more than 1700mAh. All other, and hot ones I will scrap. Thank you.
No one ever mentions the cut off voltage. All these mAh numbers are so gameable. Just multiply them on nominal voltage with complete disregard of discharge curve and hope for the best. I wish people just use Watt*hours already.
Agreed.
The cut off voltage varies with each different type of lithium technology of which there are several types. You need to consider its Ah AND its nominal voltage/low voltage/max voltage to produce a watt hour capacity for the lithium cell type
You cannot calculate watt hours. You can only measure it because the voltage is not constant
@@climatechangepreppersfaceb2148 of course you can. You take the nominal voltage and it will give you a good approximation to the watt hours given the ah of the cell. EDIT just run a test on any lithium technology like lipo or lion or li-fe whatever and take the nominal voltage and multiply with ah and the numbers resolve to Wh. A power meter in circuit will prove it for you.
@@unlost117 80% of the SOC is below nominal voltage. So no, you can't
Stop me! I might assemble a battery for my motorcycle.
Looks like 9 is the number.
I really couldn't pay attention to this. I kept expecting you to introduce someone famous on their yacht and when you didn't I was kinda let down.
Great. Thank you.
However virtually everything described is theoretical. Reality, particularly in low cost Li cells is going to be both disappointing and potentially dangerous, although other than the DIN rail setup, probably not going to explode if attempted by a beginner.
Bottom line: Unfortunately, in the Li world today, you get what you pay for. Cheap isn’t a good way to go.
What on earth are you babbling about? The exact same maths applies irrespective of what brand, type, chemistry or quality cells are used.
John Coops. It doesn't apply with the mathematics of too many online battery bank retailers. Chinese maths often bears no relation to reality.
@@RWBHere - That still doesn't make sense, and you are confusing the issue. The entire purpose of this video is to show how consumers can calculate battery capacity in Series/Parallel arrays. It's got nothing whatsoever to do with the truthfulness of sellers.
No matter what brand of cells, the *mathematics* for calculating the Series/Parallel capacity always remains the same, whether you use a >3000mAh Sanyo/LG/Samsung or some POS 800mAh no-name recycled and rewrapped crap.
Sry to be nit picky but you say your lithium ion set-up ( @ 5:30 ) is 7s20p but it's actually 20p7s. You parrelled first then series connected 20p 'arrays' in series. You didnt series connect 7 cells in series then parrell these 'strings' ( you would need 1 bms per string for this which is obviously impractical).
Thats being too picky
@@noweare1 ;P
You are correct, not picky.
I think a survey of the wider community might suggest series parallel, rather than parallel series, but I like your argument :-)
Correct. Big difference
Best explanation ever, thank you so much @Adamwelch