Battery Trickle Charge Time?

[15 Phantom S6]

My car is operating 100% perfectly, but I noticed something peculiar for the 2nd time now. I have multiple cars so sometimes when I know I will be using one particular car for a couple of weeks, I’ll throw a trickle charger on the rides I’m not using. I use the terminals in the engine bay for trickle charging.

So I was using the S6 every day for a few weeks (100+ km drive each day just for work), and when I parked the car, I threw on my trickle charger. I noticed it took over a week for the trickle charger to fully charge the battery. I’ve had this exact situation happen 2 times in the last couple of months. The first time it happened I parked the car for 2 days before I threw on the charger, I thought maybe it was the 2 days of sitting, but this last time I put it on the trickle charger immediately after parking.

On my other rides, the max I’ve ever seen it take to charge it to full after operating the car is 1 to 2 days max..

Anyone else use a trickle charger and take that long to top up the battery to full? Wondering if I need a new battery or if this is normal...

[flipnidaho]

I'd get the battery tested just to be sure.

[gk1]

What type/brand of charger?
I am using the Ctek MUS 4.3 and hardly see it take more than a few hours to get to the final "Float" stage.
The theoretical max it could take with that charger would be 46 hours to get to "Float" mode unless something was wrong with the battery. However the first 2 phases hardly ever take more than a minute making the "Bulk" and "Absorption" phases the longest with a max theoretical time of 30 hours and if I just drove the car voltage is usually good making even the "Bulk" stage quick reducing max charge time to just 10 hours.
Here are the stages for reference:
1-Desulphation-15.8V Max 8h
2-Soft Start-4.3A until 12.6V Max 8h
3-Bulk-Increasing voltage to 14.4V 4.3A Max 20h
4-Absorption-Declining current 14.4V Max 10h
5-Analyse-Checks if voltage drops to 12V 3 minutes
6-Reconditon- (I don't use this mode)
7-Float (aka charge complete)-13.0V/13.6V 4.3A 10 days. Charge cycle restarts if voltage drops.
8-Pulse-(This mode only starts after 10 days on "Float")-12.7V-14.4V 0.8-0.4A Charge cycle restarts if voltage drops.

[15 Phantom S6]

I use an "Opti-Mate 3+" and it has worked flawless for me for years.. I have 4 cars and a motorcycle I use it on and no issues with the charger at all. In fact it has saved a couple of batteries that I thought were toasted in the past from really long discharge times..

My trickle charger automatically tests the battery when it's trickle charging and will determine if it's bad or not. It indicates battery is "good" after the trickle charge is finished..

[ENV²]

I use the Ctek as well. It has a recondition mode for batteries that may be going bad and can sometimes actually save them.

Best $80 ever spent

Sent from a misfiring cylinder

[gk1]

I use an "Opti-Mate 3+" and it has worked flawless for me for years.. I have 4 cars and a motorcycle I use it on and no issues with the charger at all. In fact it has saved a couple of batteries that I thought were toasted in the past from really long discharge times..

My trickle charger automatically tests the battery when it's trickle charging and will determine if it's bad or not. It indicates battery is "good" after the trickle charge is finished..

Understood, but you see how the Opti-Mate is a 0.8A charger vs. the Ctek's 4.3A. That is why it is taking so long to charge. It appears it is really a motorcycle battery charger that you are using on a large car battery which as you've seen can work, it will just take a long time to get there. On the TecMate website they have the rating of 2Ah-50Ah batteries for the Opti-Mate3 and pictures under the charger of a scooter, a motorcycle, an ATV and a jetski, but other models with higher amperages show a car and a boat. Like the Opti-mate 5 or 6 and indicate they go up to 192Ah or 240Ah respectively. I believe the S6 battery ranges from 75Ah-100Ah.
Hope that helps.

[15 Phantom S6]

Thanks for that info… I’m ok with the longer charging time due to the lower amperage, I’m just wondering if the excessive amount of time to charge my S6 battery is any indicator of my battery strength or life. My car is running like a champ and I have no symptoms or issues at all right now which is why I thought it was strange for it to take so long to charge.

I have a lot of experience with this charger, I’ve used this charger on numerous different batteries of different sizes and in all different states of charge and none have ever taken as long to charge as the S6 battery, and the S6 battery was not depleted in any way prior to trickle charging.

I guess I’ll just keep an eye out and replace the battery if any wonky electrical stuff starts happening..