needed a charger for my car battery & stumbled across this special at Repco.
http://catalogues.repco.com.au/catalogue/repco-catalogue-win…
12v Battery Charger $21.99 (REPCO 50% OFF)
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Yep gotta make sure to turn it off or you might end up with this - http://www.powerstridebattery.com/blog//wp-content/uploads/2…
That said its a great price, I've got one myself and it gets the job done - although @ 2.7A its takes a while :)
wow, way to totally fail at understanding lead acid batteries.
lead acid batteries will ONLY take up as much charge as they need. you do NOT need to disconnect them when they are "full" they simply stop accepting any more power.
want proof? go for a 3 hour long country drive, before you turn the motor off stick a multimeter on each of the battery terminals and measure the voltage, it will be somewhere around 14.4v (ideal charging volts)…. in a vehicle the battery is always on charge. dosnt matter if you drive for 5 mins or 5 days straight.
Are you for realz?
Why to alternators have voltage regs and now days ECU controlled battery charging algorithms built in?
Why to alternators have voltage regs
to keep the voltage supplied to the battery under 14.4v… in the old days you used to get adjustable regs and anything above around 14.4 you would constantly blow bulbs
now days ECU controlled battery charging algorithms built in?
that would be for one of 2 reasons, either to save on fuel consumption and there for keep within emission standards (charge only when decelerating not accelerating there for saving on fuel/emissions) or more likely only used on these new "turn the motor off at traffic lights" cars which recharge capacitors for restarting.. which is for the same reason as example 1
again. go do some research. you look dumb…
unless of course your far more informed than those "idiots" over at wikipedia… i just used there info on "per cell" lead acid batteries and calculated the values over to 6 celled (aka 12v) lead acid batteries…
results for continuous charging (aka, 24 hours a day 7 days a week 365 days a year) are as follows…
Continuous-preservation (float) charging:
2.23 V for gelled electrolyte 13.38v
2.25 V for AGM (absorbed glass mat) 13.5v
2.32 V for flooded cells 13.92vobviously this changes if your recharging from "flat"… but you were only talking about the need to terminate charging once the battery was "full" for fear of it "exploding" as in your example picture…..
Dumb - harsh. Looking at your past posts you don't seem to be a troll so I'll address your misinformed posts for the benefit of others.
So your average car battery might bulk charge at around 13.6 - 14.0V (100A), this quickly charges the battery.
As the batteries charge reaches near full the alternator backs off the flow of current via the regulator (by adjusting the regs field current) to a 'float charge', voltage stays at say 13.8V but produces only a few amps.
You could drive your car around for a million kms (like a taxi) and the battery won't overcharge because the alternator has automatically cut its charging current.
However that doesn't mean - "lead acid batteries will ONLY take up as much charge as they need. you do NOT need to disconnect them when they are "full" they simply stop accepting any more power".
Most battery chargers effectively mimic an alternators function, they quickly charge at their maximum amperage, then once the battery reaches near full charge they switch to a 'float' topping off the battery and eventually supply no further current.
HOWEVER THE BATTERY CHARGER IN THIS DEAL does one thing, it throws 2.7A at your battery (which charges it fairly quickly) but it doesn't automatically switch to float mode. It just keeps on charging, which eventually WILL DAMAGE YOUR BATTERY
Some good, if detailed reading on battery charging stages here - http://batteryuniversity.com/learn/article/charging_the_lead…
Battery Don'ts (third point) - http://www.batterystuff.com/kb/articles/battery-articles/bat…
On overcharging - http://www.dcbattery.com/faq.html#7
and finally Wikipedia - http://en.wikipedia.org/wiki/Automotive_battery#Exploding_ba…
wow, your still actually completely wrong…
you can hook up a 200a charger to an almost fully charged lead acid battery… and it will still only "accept" an amp or 2…
in fact, you know how the leds/gauges on your chargers work? they only look at how much "charge" (how many amps) your battery is accepting and displays it. its still trying to output how ever many amps its capable of (for a certain voltage)
again, the "voltage reg" on your alternator on any car only regulates the voltage. teh alternator is still trying to output its 100+ amps that its capable of.
in fact… even looking at your link….. it says NOTHING about how many amps… only overvolt..
https://en.wikipedia.org/wiki/Automotive_battery#Exploding_b…
Exploding batteries
Car battery after explosion
Any lead-acid battery system when overcharged (>14.34 V) will produce hydrogen gas (gassing voltage) by electrolysis of water.so as per my comment above
results for continuous charging (aka, 24 hours a day 7 days a week 365 days a year) are as follows…
Continuous-preservation (float) charging:
2.23 V for gelled electrolyte 13.38v
2.25 V for AGM (absorbed glass mat) 13.5v
2.32 V for flooded cells 13.92vyou can for ever pump ~13v into a lead acid battery… and not see any "explosion" let alone any other negative effect.
like i said… the reg in cars is only a voltage reg, it does not turn off the "charging" it simply keeps the continuous charging voltage at a "safe" level of under 14.4v…
like i said.. you dont believe me? thats cool… if you have a multimeter test it yourself. no matter how long you leave your car running… you will ALWAYS see the same voltage across the terminals it will ALWAYS be charging somewhere between around 13v and 14.4 (no more than 14.4 like i said or you will end up blowing globes)
FYI, my 14.4v is what all good quality car amps are graded on. its how many watts they can produce at the max car voltage of 14.4. most car audio people (like me) will happily sacrifice 2% of battery life for 10% more RMS :)
PS Using multiple accounts to neg my comments nosdan doesn't make them any less real.
oh damn… you worked out that i am also JV and pmupsinep? you did that all on your own?
PS. its actually "ford xy gt ho" not the other way around… ;)
edit: and if you had ANY idea of how '70's cars worked.. you would know they usually had external voltage regs to keep there alternators voltage in check…. while allowing them to supply as many amps as could be taken up by there batteries :)
I know I know, it just didn't seem to roll off the tongue so well and I was young and once you pick a Nik it tends to stik!
so many negative votes yet the conversation so positive…
cornbeef 9 min ago
every time i see your nick… i cant help but think of duckman…
https://www.youtube.com/watch?v=hdHiHpYYGygwow - that's exactly what i look like and how i act!
I, dont know what to say, there is some very strange info in this thread, thats all I can say.
This charger Will over charge a car battery no matter what if you leave it on… Ive done that before, killed the battery.
nope, again you have misunderstood lead acid batteries.
Ive done that before, killed the battery.
discharging a lead acid battery is what kills it. they are FAR different to any other "rechargeable" battery.
on a "normal" (non deep cycle) battery even just dropping 1v (from 12v to around 11.5v) destroys the battery no matter how you recharge it. it destroys the plates in it.
Looks as though the guys that manufacture battery chargers and batteries are wrong then. Copied from charger manual.
"HOW BATTERIES CHARGE
A charger DOES NOT FORCE current into a battery - it makes a limited amount of current available and the battery draws as much of it as it needs, up to or slightly greater than the rated output current capability of the charger.
The closer a battery is to zero charge (dead battery), the more charging current it will want to draw. When charging begins, on a dead battery, the chargers ammeter will register toward the high end of the ammeter scale and move toward zero as the battery becomes more fully charged.
KEEP IN MIND, the ammeter registers the amount of amperage being drawn from the charger by the battery, not what the charger is capable of delivering.
One would expect a battery to draw zero amps when it reaches 100% charge. But at 100% charge, the battery will continue to draw a low level of current and convert it into heat within the battery. If left connected and charging after reaching 100% charge, the battery acid will begin to boil, resulting in overcharging and possible battery damage.
NOTE: A slow bubbling sound may be heard coming from the battery during the charging process. This is a normal condition and just another indicator the battery is being charged.
To reduce the risk of battery overcharging, it is important to thoroughly read this instruction manual."
Worth noting is be mindful about battery you have and that you would buy in the future.
This is only good for charging standard (cheap) lead acid batteries.
The more expensive batteries like calcium and gel need a different charger (smart charger) which is usually a couple hundred at least.
I learnt after buying a similar battery charger from SCA and wondered why the battery refused to charge and then looked it up and then checked the battery and saw it was a calcium one.
Not a great charger. Manual control. In other words you have to constantly watch it and disconnect it after the light turns green.