Fixing battery-pack on my drill, need battery-related assistance..

Hi good folks,

The battery on my drill is bad so I opened it to find out it consists of 4pc 18650 batteries.

On the batteries is says;
HENGSHENG POWERCELL
18650f 3.7v 1500mAh QX

I guess whats important is the discharge rate. On the bottom of the drill-battery it says 1.5Ah.

So does anyone know what kind of 18650's I need? What discharge rate I need?

And could I use 3000mAh batteries as long as the discharge rate is correct?

Best wishes

duckTape said:

Hi good folks,

The battery on my drill is bad so I opened it to find out it consists of 4pc 18650 batteries.

On the batteries is says;
HENGSHENG POWERCELL
18650f 3.7v 1500mAh QX

I guess whats important is the discharge rate. On the bottom of the drill-battery it says 1.5Ah.

So does anyone know what kind of 18650's I need? What discharge rate I need?

And could I use 3000mAh batteries as long as the discharge rate is correct?

Best wishes

Click to expand...

I am not much into batteries,i guess someone else could chime in and help you better,but from what i know you cant go wrong with higher discharge rate batteries,except that they are way more expensive but well worth it IME. If i was in your place i would get the cheapest 20A or more discharge rate.I would not waste extra cash if it is not for my vaporizer .
As for mAH i think you are safe using 3000 MAH . Ive used them on devices with stock 2200 without issue .
Edited:
I guess i was talking non-sence you should listen to KeroZen below..

1.5Ah is a capacity, not a discharge rate.

If it's a power tool, my guess is that they are using 30A cells, which are 1500mAh, otherwise they would have selected a larger capacity (but those have a lower C rate)

3000mAh cells currently on the market are 20A *at best* and closer to 18A in reality, not good if the above is true.

I'd go for LG HB6 with pink wraps >> https://www.fasttech.com/p/6654301

Thanks a lot guys, I'll order them right away

@KeroZen could those batteries be used with the Milaana?

Yes of course but capacity would be low. On the other hand it would feel like using a fresh cell for longer, as the voltage would not sag much (higher voltage = higher power output in an unregulated vape like the Mi)

No idea how many bowls per charge you would get though... seeing even with 3000mAh cells it's not glorious at all already... But it would depend on your usage pattern.

PS: I might give it a try for Science sake!

For the sake of Science I shall try too

Thanks bro

Have you tried them yet @KeroZen ? Or did you order them too?

Yes I have a pack of 4 for my personal projects. I think they are inadequate in the Milaana, I did one bowl to test, the cell started at 4.15V and was 3.75V after the session... So as I suspected, they would be good for 1.5 to 2 sessions only with my usage pattern.

@KeroZen , This might be a stupid question, but the more important it is to ask, right? Here we go;

Is it safe to solder wires straight on the batteries, or should I consider on optional solution? Will I blow of my face or will I be fine?

Normally the recommended way is to use spot welding (but even then, one must be super careful and do it right)

But if you have decent soldering skills, you should be able to do it without too much trouble. Do it at your own risk of course, and perform that outside or at least over a non flammable floor, but outside is best.

The trick is to heat the cell terminal just once, as quick as possible and pre-tin it (apply a dab of solder) Then pre-tin your wire generously. This way for the final operation, you just put the two into contact, and apply the iron a few seconds at most and everything should flow.

Applying flux on the terminals should help too. Don't forget to clean afterwards though!

PS: overall the answer is "no it's not recommended", I don't want to invite people to do dangerous things

and use a wide tip soldering iron to deliver more heat, faster. i use 1/8" tip for mucking around on the pcb, and 1/4" tip for the batteries, although i have been buying batteries with tabs already spot welded on. Must invest in my own spot welder when i go into production and order 4,000 26650 cells.