Lithium charger question...

[Bryanmc57]

Quick question... It seems like everything I read says the charging voltage for a LiFePo4 battery is 14.2 volts. When I have my charger connected to my electronics battery (30ah) my voltmeter only shows 13.4 at the terminals. Would that keep the battery from getting fully charged? Thanks.

[yam911]

My experiments with an adjustable voltage power supply indicated that my Ionic brand lithium battery would fully charge at 13.4 volts. It is just going to take longer.

Does your battery have an app where you can see the state of charge? If so, you should be able to see the SOC increasing over time when the charger is connected to it.

However, not understanding why your voltage reading is so low.

[Bass in the grass]

I thought amps charged the battery, not voltage? I don’t recall my MK PCL charging over 14v, seems like it’s high 13’s, but maybe I just didn’t pay enough attention.

[yam911]

It takes voltage to push amps. The higher the voltage the greater the amps. Within reason of course.

[Bryanmc57]

So, if a chargers specs say "Max Charge Voltage 14.6V" that's just some nominal number?

[yam911]

From a charger standpoint I would say yes.

From a battery standpoint it is a do not exceed number.

This battery charging stuff is madness IMO. On the one hand they say a lithium battery is plug and play. Whereby it is connected to a constant voltage very simple charging device known as the alternator. Then they come along and tell us some exotic charging device with top secret algorithms and charging profiles must be used.

All I know is what I have seen via my battery app. Either the manufacturer is lying to me or the app is lying.

[bobcoy]

Check the specs for your brand. All major LiFeP02 battery makers quote 14.4 being the proper voltage with a max of 14.6 and minimum of 14 to 14.2.

[Bryanmc57]

Check the specs for your brand. All major LiFeP02 battery makers quote 14.4 being the proper voltage with a max of 14.6 and minimum of 14 to 14.2.

It's an ionic charger... This is all I can find as far as specs... So, with the charger connected and charging I should see 14.4 on the battery terminals?

Max Charge Voltage	14.6V
Max Charge Current	4A
AC Inputs	110V 60Hz
Weight	4.5lbs (2.0kg)
Dimensions	8.62″ (L) x 7.25″ (W) x 4.5″ (H) 219mm (L) x 184mm (W) x 114mm (H)

[DREWTICK]

that charger does put out 14.6 and most AGM/Lithium chargers will put out 14.4 to 14.6 volts but you will not see that on the terminals until the battery is full and right before the charger cuts off , as long as the battery is accepting charge its absorbing some of that power , most of the time you will only see about 13.4 for 80% of charge then it may start to climb

[Bryanmc57]

Thanks Andy... Just trying to track down an issue...

[yam911]

that charger does put out 14.6 and most AGM/Lithium chargers will put out 14.4 to 14.6 volts but you will not see that on the terminals until the battery is full and right before the charger cuts off , as long as the battery is accepting charge its absorbing some of that power , most of the time you will only see about 13.4 for 80% of charge then it may start to climb

Which can be clearly seen if one has an app that displays charge current or if one has a clamp on ammeter.