Q&A: Battery advice

I need to replace my 12 volt batteries. My power comes from a few solar cells and the load is relatively light and not every day—a studio with 60 watts of lights (currently old quartz halogen. which are easy to now replace with more efficient LEDs) and probably a 12 volt CD/radio. Would you recommend the Jaycar SLA deep-cycle battery SB1699—or indeed what else?

Also, perhaps you may have ideas about inexpensive basic 12 volt CD or DVD players that could hook into existing speakers. I have been scrolling websites without much luck; portables seem to have their own lithium batteries which rather defeats my needs. Car stereos are too fancy, with Blu-ray etc.

Susie Edwards

Jaycar’s SB1699 might be a bit small for your use, but their next size up is 100 Ah, which is probably too large. There are a lot of battery suppliers that may have a larger range, such as www.batteriesdirect.com.au, www.batteriesplus.com.au and www.batteryworld.com.au (stores only, no online shop).

I have had a few problems with lead-acid batteries in the past being a tad flat when purchased (not good for lead-acids), although with a dozen or so cycles they usually come up okay.

But, given the falling price of lithium batteries and the fact that many are drop-in replacements for lead-acid nowadays, you might want to consider them. Examples are the 12 volt models at www.ev-power.com.au and www.evworks.com.au.

Re the CD player, you can reuse a computer CD/DVD drive (one with play and stop buttons on the front) for this sort of thing. There is an adaptor kit that lets you do this but you need electronics experience to build it; see Jaycar part number KC5459.

But if you want just simple play functions then you don’t need an adapter, just supply it with 12 V from the battery and 5 V via a small regulator, and connect the headphone output to the speakers. If they are powered speakers then you will get good volume; if not then you might need a small amplifier between the two, such as www.ebay.com/itm/140808997786 or Jaycar’s AA0487 or AA0473 (single channel only).

Of course, this is all very DIY and if that doesn’t appeal then a low-cost car stereo is probably going to be the best option.

Lance Turner

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