Batery capacity is weird

For some reason, vehicle batteries are way way less effective(*by mass) than regular batteries, even rechargeable ones. (all values are taken from latest build, 10732)
If you calculate capacity to mass ratio, all batteries that are vehicle parts will be in range 0.1-0.2 charges/g. Regular batteries, even rechargeable non-high-cap ones, are in range of 0.8-3.3, i.e. they are about 10 times better than their vehicle counterparts. Let’s not even talk about ultra-light battery with whopping 10. A freaking hundred times better than small motorbike battery, and 50 times better than mostall other vehicle batteries.
If you compare them by capacity/volume instead, then it doesn’t look so weird - while the range of values is still quite big (from 0.2 to 1.6, barring some obviously out of whack items), there is no definite winner between vehicle and regular batteries.
So, either vehicle batteries have too much weight, or regular (rechargeable) ones have too high capacity. e: or vehicle batteries have too low capacity.
Working as intended?

values for those interested
type name mass volume capacity density e.density(cap/g) e.density(cap/ml)
veh small motorbike battery 1500 750 150 2,00 0,10 0,20
veh motorbike battery 4000 1250 500 3,20 0,13 0,40
veh car battery 18000 6250 2500 2,88 0,14 0,40
veh large storage battery 400000 50000 80000 8,00 0,20 1,60
veh medium storage battery 35000 6250 7000 5,60 0,20 1,12
veh small storage battery 2500 500 500 5,00 0,20 1,00
veh storage battery 200000 25000 40000 8,00 0,20 1,60
reg medium battery (high-capacity) 725 525 600 1,38 0,83 1,14
reg medium battery 600 450 500 1,33 0,83 1,11
reg heavy battery 1000 1225 1000 0,82 1,00 0,82
reg heavy battery (high-capacity) 1250 1500 1250 0,83 1,00 0,83
reg military plutonium fuel cell 64000 3000 100000 21,33 1,56 33,33
reg medium disposable battery 725 525 1200 1,38 1,66 2,29
reg heavy disposable battery 1250 1500 2500 0,83 2,00 1,67
reg light battery 30 25 100 1,20 3,33 4,00
reg light battery (high-capacity) 45 35 150 1,29 3,33 4,29
reg medium plutonium fuel battery 1000 525 5000 1,90 5,00 9,52
reg heavy plutonium fuel battery 1600 1500 10000 1,07 6,25 6,67
reg light plutonium fuel battery 160 35 1000 4,57 6,25 28,57
reg ultra-light plutonium fuel battery 80 1 500 80,00 6,25 500,00
reg light disposable battery 45 35 300 1,29 6,67 8,57
reg ultra-light battery 5 1 50 5,00 10,00 50,00
reg ultra-light disposable battery 5 1 100 5,00 20,00 100,00

I hate to be that guy, buuuut…
What’s the ‘net worth’ of 1 ‘charge’ we have in a battery ingame? It probably ain’t plain MJ, right?

I don’t know what the exchange rate between charge and MJ is, and this makes comparing the ingame batteries and real life batteries really hard, which would be helpful with figuring out what the ‘correct’ energy density would be for the batteries in the game.

The only thing I >can< tell, is that regular real life batteries seem to have around-ish .10 to .35 or so MJ/kg, which, if changed to grams, would be 0.0001 to 0.00035 MJ/g.*
Better batteries (Looking at you, Lithium batteries), have around 0.4 to 0.7 ish MJ/kg, while som non-rechargable batteries have 1+ MJ/kg.*

– For the sake of comprehension i slightly edited this post to better reflect where I’m going with this. –

Judging by how battery charger/cable charger CBMs work, 1 charge=1kJ. But I don’t get why would you even ask this question, joules are not used anywhere in batteries descriptions, it’s all “charges”.
e:oh, wait, I get it. You though different batteries could have different charge “units”. Nope, that’s definitely not the case.

e.2: even from this table, if we’re looking at rechargeable

there’s an easy solution to your problem - don’t be him :grin:

I’m asking in order to be able to compare it with Real life batteries.
In your first post, you calculated the energy density, by using the capacity of the batteries - means, the maximum amount of ‘charge’ they can hold, and divide it by weight or volume.

I on the other hand basically try to figure out if the batteries are close to their real life equivalents, thats why I’m trying to convert it to Joule. Probably should have made this more clear.
As I said in my other post, the regular energy density of batteries would be anything between 0.1 and, lets say ~1 MJ/kg, or 0.1 - 1 KJ/g.
Therefore, looking at your own table, the vehicle batteries seem to be realistic ones, while most of the regular inventory-batteries are way too good.

This, in essence, means the vehicle batteries don’t have too low of a capacity, the regular batteries are just ‘too good’. That’s more or less what I was trying to figure out with my chain of thought.

The logical step would therefore be to lower the regular batteries capacity, which would break most of the power-using tools though, since they’d be, in essence, way too powerhungry all of the sudden.

now breaking off from my train of thought, the values are most likely relatively arbitrary, and are just put in place because they ‘work’. They don’t want you to switch out batteries every 2-3 hours because the battery-life is too short, and they don’t want 1 car battery be worth a million normal batteries, that’s probably the main reason why they chose these numbers.

The correct thing to do would be to increase the mass and volume of regular batteries without changing their charge capacity.

Please submit a patch so people can argue about this, but it’s pretty clear the ultralight batteries are way too good.

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and having battery the are heavier then the flashlight …not really going to work is just problem balance but still make no sense but you know what game to make sense all the damn time not going to work out why to be fun need some thing to be unrealistic because begin realistic all the damn time is boring and hard to code everything for the happen (charge system need complete overhaul to work now is to much of mess)
edit%1 correcting some grammatical error sorry not native speaker

That argument is simply invalid, either because this is already the case (medium/heavy battery) or because even doubling the weight/volume wouldn’t make it heavier than a flashlight (light/ultra-light).

In Comparison:

name weight volume
Flashlight 0.4KG 0.5L
Heavy Battery 1.0KG 1.225L
Medium Battery 0.6KG 0.45L
Light Battery 0.03KG 0.025L
Ultra-Light Battery 0.01KG 0.01L

You could easily double the weight and volume of the Light Battery and triple or quadruple it for the Ultra-Light, and it would still be ways lower than the weight of a normal flashlight while getting their E-Density closer to the other batteries.

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Look im not really trying to say battery will be heavier the flashlight just point out not really working out if just increase the weight all battery because the problem is system keep on changing and not begin complete overhaul

True. Flashlight is just a plastic case and (nowadays)LED light emitter. None of those take much weight,

But they can be heavier, even IRL.


can some grab AA battery weight for me

battery wiki AA cell

Bogdan, you need to learn how to quote properly. Sorry bud. And how to EDIT your posts.

23g for normal Alkaline ones, 15g for Lithium and rechargable are around 31g. You usually put several of these in a flashlight, so it’s actually pretty reasonable to assume that the batteries can weigh just as much as the flashlight, if not a bit more.


so just increasing the battery weight going to work to solve charging problem or…what?

and correct mean if im wrong but car battery charge has be reduce for balance reasons??? not for being more realistic

It’s going to bring regular betteries in line with their vehicle counterparts. And also make the game harder. Isn’t it what we all strive for? /s

not really harder just more annoying to deal with …

The Vehicle Parts are fine, it’s the normal batteries which are a concern, especially the light and ultra-light variants.

I would argue that heavy and normal batteries can stay the same, as they tend to stay within a reasonable limit of the other batteries.
Only the Light and Ultra-Light batteries are, in comparison, way too good.

Not sure about that. I didn’t play for a year, but the batteries were basically all there back when i played - and i rarely used ultra-light batteries. I had 1-2 light batteries for stuff like MP3 players, but most of my tools were filled with medium or heavy batteries, so I’d argue it’s not that much of an issue, since you can still use the medium or heavy batteries like you always did.

the argument start comparing how good are light battery compare to one vehicle per weight and yes not really begin problem

But i trying to aruge the system is problem because is not finsh and is going to change so just adding more random stuff changing stuff is going to make take more time for it to change

Nonsensical argument again.
We’re not adding anything to the battery system, we’re talking about changing values of existing items. Changing them takes barely any effort, one just has to find the values in the files and change them.

And even if we were to add anything - which we aren’t - it would just be simple items, you can add, change and remove those with a few clicks.

On a sidenote, we’re not adding or changing ‘random stuff’ as you call it. It’s items that are already in the game which might be changed slightly - maybe to an extend you won’t even realize - and that happens on a near daily basis when contributors are working on the game. You apparently think this whole change is enormous, and it takes tons of time to do it or reverse it, but thats simply not true.

Go into your Cataclysm folder, into data/json/items. Click on any file in there, I dare you, and look at it for a few moments. It’s basically just replacing a number. The most time-consuming part would be to find the batteries and make new weights and volumes which make sense, and even then, I’d argue there are backups so the contributors can easily revert any change if they don’t like it.