Battery Charging - Red Top Optima - float at 2 amp?

[phantomracer]

Yea I know the quality of these batteries is suspect as of late. My starting battery is a 6 year old Optima red top, and seems to be holding its own .

Pulling the boat out soon, I was curious what Optima said about their charging requirements..so i looked it up.. it seemed odd to me.. Then again, I am not the brightest bulb on the tree sometimes!

from: Optima battery charging

Cyclic Applications:
14.7 volts, no current limit as long as battery temperature remains below 125°F (51.7°C). When current falls below one amp, finish with two-amp constant current for one hour.

Correct me if I am wrong...If you charge CC to get to 14.7v, wouldn't it go to CV til the amps went down (to <1a or so)...

How can you charge at CC at 2.0a AFTER getting to 14.7v without the voltage spiking? Or is that what they are saying, they want to spike the voltage for an hour after

[PaulCrawhorn]

Yes, poorly worded. The max voltage must be capped for safety.

The battery determines what current gets pulled, the source only offers up to a maximum.

I would interpret as

"Hold Absorption/CV voltage for an additional hour after current trails below 1A, before terminating the charge cycle / dropping to Float stage"

[PaulCrawhorn]

There would likely be no harm raising voltage a little, say up to 14.9V for that last hour in order to encourage higher current flow.

In which case I would interpret 2A as a maximum spec.

Getting that "last bit of Full" will be good for longevity, with all lead chemistries.

Too often - by default with most chargers - the charge cycle is terminated way too early

[phantomracer]

Plus since 90% of people do not have chargers that can control volts or amps, just 'automatic' , it really means nothing to most people. They plug in their automatic charger and watch the light show!

Maybe the directions were originally written in Chinese and something got lost in the translation! haha!

OK, so it is not just me that finds the working problematic! I thought I was missing something!

Last few years I have been using a power supply to control the charge for the boat batteries.

I did just buy this for my cars, seems to be a good compromise, but it is a manual charger. Works similar to the power supply but smaller and lighter.
https://www.amazon.com/gp/product/B09FSSBZZ4/

[PaulCrawhorn]

Auto charge termination is a must IMO.

As is a temp based cutoff.

[Lostsailor13]

In Victron chargers you can select user defined and tweek all three charge stages

[smac999]

Originally Posted by Lostsailor13

In Victron chargers you can select user defined and tweek all three charge stages

they do not do constant current. no marine charger would do it. you'd need a bench power supply or something to follow the guide line posted.

since that constant current voltage would have to be higher then the bulk voltage it seems it's their way of doing an equalization charge .

[PaulCrawhorn]

CC just means Bulk stage, prior to hitting the Absorption / CV setpoint.

It's actually a misnomer in this context never means literally "constant" amps rate