smart way to charging batteries.

[hacknet]

hi, i have seen that batteries are in fashion now.

can anyone reccomend to charge 2 12v batteries when they run dry. i`ve seen a couple of circuits but all only charge single 12v batteries.

i intend to use the 2*12v to power a preamp with split rails.

[Steve Eddy]

Originally posted by hacknet
hi, i have seen that batteries are in fashion now.

can anyone reccomend to charge 2 12v batteries when they run dry. i`ve seen a couple of circuits but all only charge single 12v batteries.

i intend to use the 2*12v to power a preamp with split rails.

If you really want a "smart" way to charge batteries, I'd recommend using one of the smart multi mode chargers based on power management ICs as opposed to simple trickle chargers. The smart chargers allow for optimal charging and increase battery life.

I also use a pair of 12 volt SLAs for a split supply and use a Patco IntelliTender 300 which is a dual charger and can charge two batteries simultaneously. DigiKey sells it for $124.88 plus the cost of the cable (you can choose between spring clamps or ring lugs).

Ain't exactly cheap, but it's a damn good charger and will perhaps save you money in the long run if you plan to continue using SLAs. And all you need is a four pole switch and switch the batteries between the preamp and the charger. Just use it as you'd use a power switch and your batteries will always be topped up.

Good luck!

se

[georgehifi]

I run my d/a convertor (which consumes 500ma continuious, class A discrete output stage) on 2x 12v batteries in series to give me 12+ ct 12- and i charge them with your standard 12v charger that has an auto cut off when the battery is charged, i use 2 of them in series also to give me the same as the batteries + ct - i`ve been using them now for two years and no problems yet the batteries still charge up fine after 3hrs of listening, i had to change the + and - regulators for more expensive low dropout types but it was all worth the effort for the super black background you hear between musical notes, and a percieved increase in dynamic range whether from the black noiseless background or the big current delivery the 2x 12ahr batteries can give.
Cheers George

[Peter Daniel]

I was wondering if you can charge two 12V batteries in series, if you have 24V charger?

[georgehifi]

Peter that`s exactly what i`m doing with 2x12v auto cheap burgular alarm chargers from Radio Shack, Tandy, Dick Smith, or Jaycar. The 24v auto charger does`nt exist at these cheap retail outlets

[Peter Daniel]

I'm using four 12V batteries for +/- 24V rails. I have two 12 V chargers, but to charge the batteries I have to rearange the connections and I'm charging ea bettery separately.

But I could simplify all that if I build two 24V chargers and charge everything at once, without a need for switching connections and so on. The batteries would have to be charged in series though.

EDIT: Actually somebody already answered that to me and some details of charger could be found here: http://home.tiscalinet.ch/cooltune/P...Megalith01.htm

[georgehifi]

Peter just get another 2 cheap 12v chargers and hook them all up in series with the batteries, each battery will look like it`s got it`s own charger.

[cowanrg]

a co-worker and i were talking about this today. i have posted my charger for my preamp around 10 times... yet people still ask this question. its odd. if i can figure it out, its really easy!

[Peter Daniel]

Maybe those people didn't like your charger.

[Peter Daniel]

Originally posted by georgehifi
Peter just get another 2 cheap 12v chargers and hook them all up in series with the batteries, each battery will look like it`s got it`s own charger.

I don't want to charge batteries separately. I want to charge them from 24V supply, which can also be used to power the amp, if batteries for some reason become dead.

I was also thinking about some smart, multi mode chargers based on power management ICs as opposed to simple trickle chargers, allowing optimal charging and increase battery life.

Not something simple, that even cowanrg can figure out