SSG model: battery charging problem

[bryanx78]

hi!
I try to recharge a lead battery (12v - 5ah) with my ssg model. Voltage increase speedly, but when i turn off my circuit (when battery voltage arrive to about 15v!), voltage battery drop to about 12,4v!!!
Is normal? How much i must go up?

Thanks!

[BroMikey]

hi!
I try to recharge a lead battery (12v - 5ah) with my ssg model. Voltage increase speedly, but when i turn off my circuit (when battery voltage arrive to about 15v!), voltage battery drop to about 12,4v!!!
Is normal? How much i must go up?

Thanks!

ANSWER: RESTING voltage = 12.7v - 13.2v

[Aaron]

resting voltage

hi!
I try to recharge a lead battery (12v - 5ah) with my ssg model. Voltage increase speedly, but when i turn off my circuit (when battery voltage arrive to about 15v!), voltage battery drop to about 12,4v!!!
Is normal? How much i must go up?

Thanks!

It is normal for battery voltage to drop and settle like that after charging - that will happen even with conventional chargers. If you have a resting voltage of 12.4 volts, it's in fairly good shape. At 5ah, is that a gel cell? If so, 14.8 is about as high as you want to push it.

If you want a higher resting voltage, if the battery can be brought back more, discharge with a 20 hour rate = 5ah / 20 hours = 0.25 amps x 12v = 3 watts. If you put on a 3 watt load on that battery after fully charged, let it bring the battery down to 12v then recharge it fully again and repeat a few times. Each time, that battery should have a bit higher resting voltage each time.

[bryanx78]

At 5ah, is that a gel cell? If so, 14.8 is about as high as you want to push it.

thanks for help! no, it's a normal lead battery... I must change max charge voltage?

[Aaron]

flooded cell voltage

thanks for help! no, it's a normal lead battery... I must change max charge voltage?

If it is a flooded cell battery, then push it to 15.3 volts.

[bryanx78]

If it is a flooded cell battery, then push it to 15.3 volts.

no, it's AGM cell battery... is the same?

thanks a lot!

[Aaron]

Agm

no, it's AGM cell battery... is the same?

thanks a lot!

AGM is closer to a gel cell - 14.8 is the max they should be pushed. If it is a newer battery, I wouldn't go past that, but if it is old and warn out, I'd push it a bit higher if you don't have anything to lose.

[bryanx78]

If you want a higher resting voltage, if the battery can be brought back more, discharge with a 20 hour rate = 5ah / 20 hours = 0.25 amps x 12v = 3 watts. If you put on a 3 watt load on that battery after fully charged, let it bring the battery down to 12v then recharge it fully again and repeat a few times.

i'm trying to discharge my battery with a 3 watt lamp, but under load, voltage drop to 11.9v in few seconds (but without load it return to about 12.4v in few seconds).
Do you think my battery is warn out?

[Aaron]

discharge deeper

i'm trying to discharge my battery with a 3 watt lamp, but under load, voltage drop to 11.9v in few seconds (but without load it return to about 12.4v in few seconds).
Do you think my battery is warn out?

If it is AMG and has an amp hour rating, it is probably deep cycle and you can draw it down to 10.5 volts. Keep that 3 watt lamp on there and discharge it down to 10.5 v then charge back up to 14.8 v and then put the lamp on again. Does it bottom out again? I'd repeat that a few times.

[bryanx78]

If it is AMG and has an amp hour rating, it is probably deep cycle and you can draw it down to 10.5 volts. Keep that 3 watt lamp on there and discharge it down to 10.5 v then charge back up to 14.8 v and then put the lamp on again. Does it bottom out again? I'd repeat that a few times.

ok, perfect! Thanks!

If i use a flooded cell battery (i want buy a new one!), how much i must go down before restart the charging cycle?