Make my own diy battery

hi, im thinking of making my own battery. the idea is to use at about 2 or more VEEKTOMX Mini Power Bank:
and make a 3d print case for it. the real problen is that i want to use only one usb port on my Framework Laptop 13, 11 gen. i cant find a labtop dock that has 2, 60 w pass through. and any ideas for better battery bank can also help. thats all and thanks!

So you will get a max of 9V from one of those. PD 3 doesn’t use 12V and it doesn’t say what the PD output is anyway. So you will get a max of 20W if you are lucky.

Type-C Output 5V/3.0A 9V/2.2A 12V/1.5A

Presumably you are not going to put them in series so parallel ? which is why you want a dock.

So with a dock is this meant to be a portable option which begs the question of use, how long do you have to be a way from a mains power source to carry 2 or 3 batteries and a dock. Are you sure a straight single battery would not be more convenient and useful?

Also the dock has to negotiate 2 or more batteries.

What output do you want the dock to output, do you want it to have electronics to up the volts or a straight through connection type.

Check out other topics etc.

Thank, I didn’t realize that it didn’t have enough watts. And I makeing my own case that will hold the docks and more. But the downside is that is too small to use the framework battery. I need at max battery 20.5 cm long, 8 cm wide and 3 cm thick. If I find one big battery that also fixes the dock.

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Browsing on my 11th Gen doesn’t use 20W, heavy stuff and charging would show up the limits.

12v support was never removed from PD. Mandatory support for 12v was removed after PD 1.0, but optional support is still present.

Afaik 12v PD is fully supported on Framework laptops. 15v PD was removed through a software update on 11th gen due to a chip that Framework was using entering a bugged state if the charger voltage was too close to the battery voltage (15.4v nominal).

Nitpick: The Framework Laptop 13 only supports PD 2.0, so PD 3 is irrelevant. PD 3.0 is for PPS (which allows for chargers to support a range of voltages rather than a fixed list) and PD 3.1 is for above 100w.


Thanks for that, so I looked furtrher

USB PD 2.0 and 3.0 in comparison

The difference between the two versions of USB Power Delivery (also called USB-C Power Delivery because of the connection) is how much information is exchanged between the charger and the connected device. While both versions communicate the maximum performance for the fast charging process, USB PD 2.0 is mainly limited to this exchange.

With USB PD 3.0, information on the charging status of the device battery, failures, overvoltage, battery temperature and / or other details is also exchanged. This makes it possible to adapt the charging process to certain factors. Errors and system changes are therefore taken into account when charging the battery when using USB PD 3.0.

In addition, the device can inform the user if there is an irregularity - for example a message if certain factors slow down the charging process, if there is too much voltage or too high a current. If the device transfers its charge level to the charger, this can reduce the power when the battery level is high in order to charge the last percent of the battery more slowly. That saves the battery.

They look too small to be 10000mAh in any even half honest way to me.
The fact that they’re quoting mAh for a device that hopefully outputs different voltages is highly suspect for a start. The only thing to quote that has any definite meaning in this case is some proper unit of energy, like Wh. Anyway, the Chinese pretty consistently quote ridiculously large mAh figures even for things like bare Li-ion cells where the figure has a definite, well-defined meaning. A torch I bought fairly recently came with a 18650 cell in it marked 8800mAh. It’s as light as a feather, so light that it must basically be some tiny cell inside an empty 18650 size shell and I doubt it’s really even as much as 800mAh. I replaced it with a more honest, well known Japanese brand 3400mAh cell.

I find a better battery form ugreen:

It looks like it fix all my problems. Thank you all

It still doesn’t actually say at what voltage it provides 25000mAh so you have no idea if it’s totally uselsss or really good.

3.6 V.

Initially all USB battery banks used a 3.6 V battery internally so battery banks just listed the mAh.

Over time USB battery banks started using other voltages internally (7.2v and 10.8v are common), however manufacturers wanted to continue using mAh.

So when a company advertises a battery bank as “25000 mAh” what they actually mean is “equal capacity to a 25000 mAh 3.6v battery”.

It is a horrible misuse of units (they should just be using mWh or Wh), but it is unfortunately a common practice in the industry.

All battery I was looking use mah to show size. I think kyle is right and it’s used for marketing. I doubt that I’m getting scammed since ugreen is a good brand.

mAh is the rate of discharge (C1) i.e. what it can provide in 1 Hr

The wattage is that times the Volts which may be 4V so you will have 40W
As the battery charges at 60W and > 16V you will have less than 10W of power to charge the battery, more likely 7W given efficiency

C1 is a standard often used for Li-ion batteries - relatively fast.

C20 is what can be produced over 20 hours, a common term used for lead acid batteries.

The battery you link to @ C20 > 500mA for 20 hours approx, although the slower rate provides a larger wattage as it is less stressful

No. Current in mA or A could be called the rate of discharge. The current from the mAh rating is the rate of discharge that can be provided FOR one hour after which the cell will be fully discharged.


And in this case the mAh was 10,000, so I can’t see what error you see.

You could say “the battery will be discharged IN one hour” but the way you said it is just not correct English.

mW is a rate of energy transfer (aka power or rate of discharge).

mA is is mW divided by the battery’s voltage.

mWh is a quantity of energy. 1 mWh means that it can deliver 1 mW of power for 1 hour, or 0.5 mW of power for 2 hours, or 2 mW for 0.5 hours, etc (assuming no internal inefficiencies, in reality when operating at higher output power internal inefficiencies increase slightly).

mAh is mWh divided by the battery’s voltage, although USB battery bank manufacturers misuse it as mWh divided by 3.6.

mAh is not the discharge rate.

While I have seen it occasionally misused like that (and the first Google search result does say that), the C-rate is actually the inverse of that.

C-rate is the ratio of the load on the battery (in mW or mA) divided by the capacity of the battery (in mWh or mAh).

For example if I had a 10000 mAh 3.6v (36 Wh capacity) battery and I run a 25000 mA 3.6v load (90 W load) then it is operating at a C-rate of 2.5 (25000÷10000, 90÷36) and will be discharged in 24 minutes (60÷2.5).

Lead acid battery are often used for very short but high discharge loads such as starting an engine, so those are rated for C-rates of 20 or even higher. C20 is how much power a battery can sustain in 1/20 hours (ie. 3 minutes) before being discharged.

Battery capacity is usually rated based on the internal inefficiencies that occurs at C1 (higher C-rates = more internal inefficiencies), which is why C1 is often mentioned on the capacity ratings.

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I suppose I’m used to the language of old, and off grid for 40 years. I buy lead acid batteries with Ah and C rating i.e. 250Ah : C20 meaning it will last for 20hr at a specific discharge rate. Of course most of these batteries were 12V pretty standard so everyone spoke the same language. Now with multiples of 3.6v to 4.5v being common mAh and Watts are used. ‘We’ never used watts as it was 12v and 250Ah @ C20 so we knew it was around 3Kw @ C20.

I mean ‘we’ bought batteries by the voltage 6v, 12v, 24v so we just then went by size as 250Ah

Consider the 100 Amp Hour battery. As indicated above, it will provide 5 amps of current for twenty hours while maintaining a voltage above 10.5 volts. A common mistake is made when it is assumed that the 100 AH battery will also provide 100 amps for 1 Hour. It won’t. In fact, a battery of this type may only provide about 40 minutes of continuous 100 amp service at best.

That’s the C rating of 20.

You may describe LI-ion batteries alternatively, but the 10Ah battery mentioned should provide @ C20 approx 500mA or at C1 10A at it’s design voltage.

So yes you may have a different use of English, mine is old UK standard and I hope it wasn’t too confusing for you.

I still don’t get what it is you have a problem with but I can see you have so will end this conversation and mute this topic so as not to further ~ it is going a bit off topic :slight_smile:

Thanks bye

“in 1 hour” is not the same as “for 1 hour”.
I am English too.

Compare “I’ll be there in 1 hour” with “I’ll be there for 1 hour”. Very different.

You seem to know all this but just explained it before in what seemed to me to be a slightly weird/sloppy way earlier.

But TBH, it is difficult to explain perfectly.