your ways for power supply

[bernte_one]

hello,

for the last projects i made i often use 12V power supply. The easiest way was to put eight 1,5V batteries or ten 1,2V in a batterieholder and use it- no problems most times but too easy.

So why dont make another type of accu pack?
I bought some used notebook accus packs from *bay the have most time six 18650 accus in it. Round 3,7 V per piece and high capacity.
But one problem is to get a battery holder for them (some available on the net are very expensive) so i cut a baby cell holder (4cell) in the middle and mod it for 18650.

Next problem is the high current- four times 3,7V makes 14,8V that are 2,8 more i need.
I think i should not be critical to give Surf Pi or TGSL higher voltage?
But i plan to regulate the voltage by using an 78l12 cicuit in the accu box (some plans in the datasheets of producer).

What are your ways for power supply.

[taliesin]

current draw

hello,

for the last projects i made i often use 12V power supply. The easiest way was to put eight 1,5V batteries or ten 1,2V in a batterieholder and use it- no problems most times but too easy.

So why dont make another type of accu pack?
I bought some used notebook accus packs from *bay the have most time six 18650 accus in it. Round 3,7 V per piece and high capacity.
But one problem is to get a battery holder for them (some available on the net are very expensive) so i cut a baby cell holder (4cell) in the middle and mod it for 18650.

Next problem is the high current- four times 3,7V makes 14,8V that are 2,8 more i need.
I think i should not be critical to give Surf Pi or TGSL higher voltage?
But i plan to regulate the voltage by using an 78l12 cicuit in the accu box (some plans in the datasheets of producer).

What are your ways for power supply.

as long as your circuit doesn't exceed the current rating of your regulator you should be ok.your capacitors should be adjusted accordingly that see the higher voltage.if your concerned about the volts drop it with a few diodes in series.how do these accus compare in size to the usual aa's ?

[bernte_one]

Hello,

the size of 18650 accus is a little bigger as the aa cells so that they dont fit in an aa holder but the have a higher charge. Other way could be to use 14500 cells they are mostly same size as aa (+1 till 2mm when overcharge protection is built in) but the have only 900mAh.
The 14500 accu pack could be the absolut lightweight. but at the moment in my opinion to expensive. Look at http://s.dealextreme.com/search/14500

greetings

[taliesin]

i've done this with odd size batteries

it can go inside the metal detector stem or clipped on with bike pump holders

[bernte_one]

hello taliesin,

i made it his way for bicycle flashlight. Good trick is to connect the batteries with thin neodym magnets (dia 8mm strenght 2mm).

[taliesin]

nice

i'll try the magnets