Glad it does. Thanks!

I tried my best! Cheers.

He did well, but he got wh wrong

Thanks Colin.

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?

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.

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

john goulsbra - Exactly.

You can try me - although I don’t use outback kit.

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 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.

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.

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

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.

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.

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