small high output Li-ION batteries?
JBWolf
Posts: 405
Hello,
I need a solution for batteries but am limited by diameter of the project container they go in... it's a tube.
My project runs off 5v or greater... needs a minimum of 1.75 amps, and can be no wider/diameter than 10mm.
Preferably I would like to go with Li-ion. The reason for this is because I am powering LED's (lots) and would like to avoid dimming as the batteries discharge.
The closest I have come to a solution this far is:
a single 12v A23 2000mah battery
or 4x 10440 (AAA) Ni-MH 800mah batteries
I have tried the A23 batteries... they do the job, but start dimming quickly and die within 1-2 hours... and are not rechargeable.
I was thinking of ordering the 10440 ni-mh batteries, but havent researched if they discharge like a Li-ion battery (full output till drained).
the only thing I dont like about the 10440 (assuming they go full output until drain like li-ion), is that they are 1.2v which means I need 4x of them to equal 4.8v (that will work for 5v).
Does anyone have a recommendation?
What I would love to find are 2.5v 1200mah batteries in a AAA or AAAA size... or better yet the A23 size.
Also, does anyone know if you can charge li-ion batteries while they are connected in series?
Thanks!
I need a solution for batteries but am limited by diameter of the project container they go in... it's a tube.
My project runs off 5v or greater... needs a minimum of 1.75 amps, and can be no wider/diameter than 10mm.
Preferably I would like to go with Li-ion. The reason for this is because I am powering LED's (lots) and would like to avoid dimming as the batteries discharge.
The closest I have come to a solution this far is:
a single 12v A23 2000mah battery
or 4x 10440 (AAA) Ni-MH 800mah batteries
I have tried the A23 batteries... they do the job, but start dimming quickly and die within 1-2 hours... and are not rechargeable.
I was thinking of ordering the 10440 ni-mh batteries, but havent researched if they discharge like a Li-ion battery (full output till drained).
the only thing I dont like about the 10440 (assuming they go full output until drain like li-ion), is that they are 1.2v which means I need 4x of them to equal 4.8v (that will work for 5v).
Does anyone have a recommendation?
What I would love to find are 2.5v 1200mah batteries in a AAA or AAAA size... or better yet the A23 size.
Also, does anyone know if you can charge li-ion batteries while they are connected in series?
Thanks!
Comments
http://www.batteryspace.com/li-ion10440cylindralcellaaasize37v350mahlc-10440.aspx
Those would not meet your peak current requirements though.
14650 cells are 14mm diameter, same as an AA cell but a bit longer. Those might meet the requirements.
http://www.batteryspace.com/sanyoli-ion14650cylindricalrechargeablecell37v940mah75aasize347wh.aspx
You need to add a circuit board that prevents over discharge and protects against short circuits, and there are shrink-wrapped packs available that include the circuit. The packs with the circuit can be charged in series, using a charger made for that purpose.