Can I use a basic RC charger to charge laptop batteries ?

[user33331]

Hello
Can I use a basic RC charger to charge laptop batteries with alligator clips ?
I have SKYRC iMAX B6AC and use it to charge radio controlled RC cars' LiPos and such...

 

[qubit]

Don't even think of doing it.

Most likely the wrong voltage and it wouldn't be regulated properly anyway. You could quite easily have an exploding battery. Very dangerous.

You should only charge a laptop battery with it attached to the laptop and the laptop connected to a genuine brand charger, ie the same brand that made the laptop.

 

[dorsetknob]

Just spoke to MacGyver 's Finnish kissing cousin (Hanna Mckupski) and he said it would not end well

He said laptops input 17 to 19 Volts and use stuff inside laptop to charge Battery safely

How ever if you want to build a DIY Li-ion Bomb its worth a go

 

[trog100]

a lithium cell is a lithium cell.. basically 4 volts per cell.. 4.2 max charge 3.2 minimum or thereabouts.. most RC chargers will handle from one to six cells.. roughly 4 to 24 volts..

so with the right connectors its could be done.. but its not something i would attempt myself.. with the right connections the RC charger would take over all the needed charge controls..

balancing the cells would be the hard part.. in all far too much pissing about than its worth.. on second thoughts forget the idea.. he he..

trog

 

[kastriot]

In the specs of your charger says 1-6 LiPo cells max and 11-18V 50W max so i guess you can charge batteries but only if they have max 6 cells inside.

 

[trog100]

In the specs of your charger says 1-6 LiPo cells max and 11-18V 50W max so i guess you can charge batteries but only if they have max 6 cells inside.

lipo batteries are weird.. fully charged they are mostly 4.2 volts per cell.. they always get quoted as 3.7 volts per cell which is way less than they are when fully charged.. that six cells is really 25.2 volts.. i tend to think of them as 4 volts per cell.. it makes life easier.. why they get quoted at a half flat figure i havnt a clue..

trog

 

[taz420nj]

lipo batteries are weird.. fully charged they are mostly 4.2 volts per cell.. they always get quoted as 3.7 volts per cell which is way less than they are when fully charged.. that six cells is really 25.2 volts.. i tend to think of them as 4 volts per cell.. it makes life easier.. why they get quoted at a half flat figure i havnt a clue..

trog

Because it is the nominal usable voltage. A lithium cell's discharge curve is very flat - it holds at 3.5-3.7v through about 85% of its cycle. When fully charged and put into use, it drains quickly from 4.2 to 3.8, then holds steady until it hits about 3.5 and then drops quickly again to 3.0.

Laptop packs use a series (and parallel for high capacity packs) of 18650 Li-Ion cells. Lipo cells are the flat "pouch style" batteries found in tablets, phones, and ultra-thin laptops. Laptops usually have between 6 and 9 pins on the battery connector. 4 of them are the straight charge voltage (paralleled + and -) and the rest are for the battery management system inside the battery. You can't charge the cells directly from that connector because without the control signals the BMS won't allow anything through. You'd have to open the battery case and bypass the BMS to use an external charger. Lot of work for absolutely no gain.

 

[qubit]

You'd have to open the battery case and bypass the BMS to use an external charger. Lot of work for absolutely no gain.

Don't forget to add friggin' dangerous with the risk of fire or explosion. That's really all that matters here.
Great explanation of how these batteries work. I've learned something today.

 

[ExV6k]

Because it is the nominal usable voltage. A lithium cell's discharge curve is very flat - it holds at 3.5-3.7v through about 85% of its cycle. When fully charged and put into use, it drains quickly from 4.2 to 3.8, then holds steady until it hits about 3.5 and then drops quickly again to 3.0.

Laptop packs use a series (and parallel for high capacity packs) of 18650 Li-Ion cells. Lipo cells are the flat "pouch style" batteries found in tablets, phones, and ultra-thin laptops. Laptops usually have between 6 and 9 pins on the battery connector. 4 of them are the straight charge voltage (paralleled + and -) and the rest are for the battery management system inside the battery. You can't charge the cells directly from that connector because without the control signals the BMS won't allow anything through. You'd have to open the battery case and bypass the BMS to use an external charger. Lot of work for absolutely no gain.

Thanks for the explanation. I learned something today!

 

[trog100]

Because it is the nominal usable voltage. A lithium cell's discharge curve is very flat - it holds at 3.5-3.7v through about 85% of its cycle. When fully charged and put into use, it drains quickly from 4.2 to 3.8, then holds steady until it hits about 3.5 and then drops quickly again to 3.0.

Laptop packs use a series (and parallel for high capacity packs) of 18650 Li-Ion cells. Lipo cells are the flat "pouch style" batteries found in tablets, phones, and ultra-thin laptops. Laptops usually have between 6 and 9 pins on the battery connector. 4 of them are the straight charge voltage (paralleled + and -) and the rest are for the battery management system inside the battery. You can't charge the cells directly from that connector because without the control signals the BMS won't allow anything through. You'd have to open the battery case and bypass the BMS to use an external charger. Lot of work for absolutely no gain.

sorry put you are wrong on that one.. i play with RC toys and check voltages enough to know they dont behave as you say they do.. they just go down in a linear fashion.. the quoted voltage is just the halfway point.. i have come across your explanation before though.. but sadly it is total bollocks.. he he..

i do speak from experience and not from what i have read by the way..

trog

 

[taz420nj]

sorry put you are wrong on that one.. i play with RC toys and check voltages enough to know they dont behave as you say they do.. they just go down in a linear fashion.. the quoted voltage is just the halfway point.. i have come across your explanation before though.. but sadly it is total bollocks.. he he..

i do speak from experience and not from what i have read by the way..

trog

Uh. No. I didn't pull that out of my ass, the reason you've read it before is because that's how they work. Seriously, you think Tesla would use a cell with a linear discharge curve in their EVs? Their battery packs are made up of hundreds of 18650 cells. Lol if you believe that, I have some oceanfront property in Kansas for sale that you'd love.