I'm wondering what is the best way to supply 12V from batteries. I could use a 9V PP3 and two AA batteries but it seems a bit cumbersome. Ideally I'd like one battery which was rechargeable and had a reasonable amp/hour rating.
How much power do you need? How accurate does the 12 V have to be? Alkaline batteries are considered flat at about 1.0 - 1.2 V per cell, so if you need 12 V all the time, you need about 12 cells so two PP3s in series might be quite good.
It is to power an audio amp, I need 10V minimum but more volts is ok. I'm currently using 4 of the PP3 batteries but the leads from them are a bit cumbersome and I don't need 36V. Ideally I'd like 12V with a bigger amp hour rating. Thanks.
I know that radioshack sells recharable 12v batteries, but they are big, just a little bigger than a latern 6v. You could just use a wall wart, or whatever you call them. I ditched batteries about a year ago and now I stock pile those for all my projects.
You could get a 12v SLA battery from the likes of Maplin, plus a charger too if you don't have one.
Or.........
You could get a cheapie cordless drill from Aldi or Lidl for around the same price and use the battery pack & charger, plus you'll have a geared DC motor to use for robotics if that is one of your interests.
I have seen them at Maplin for about £17, I can get a similar one online for £12. The good thing about Maplin is that the quality of what they sell is often the best and returns are easy. Will have to decide if I want the convenience and quality or best price.
I already have a cheap 12V drill, using the charger on that is an excellent idea! I looked at the price of chargers in Maplin and it was £20, looked at car battery chargers and it is the same price.