Battery Charger

[DonD]

I used a wooden brush handle that I clean my wheels with, to wedge under the plastic cover that is over the positive connection. It gives you just enough room to use a small ratchet or open end wrench to remove the nut on the positive . It did take me about 40 minutes to get it done. The dealer tech is full of crap about half a day. With the correct tools , it can be done in under 2 hours even if you are a novice.

Are you saying the dealer said that your workaround at the battery would take half a day? Dealer guy is referring to the grey covering that is all over the trunk area. By no means am I being critical of you here, just wanting to make sure I understand all of your post.

While I'd still prefer to have easy access to the battery terminals themselves, right now my best option seems to use the connections under the hood. I used a Dremel and a file to shave down the plastic cover on the red/positive alligator clamp on my big Sears Craftsman charger (2, 15 and 45 amps) so that I can get a good connection.

Charger also has an AGM setting. Charger said 95% charged so I removed it. Drove the car, everything is fine. Don

 

[bloominguez]

Meanwhile I'm just sitting here wondering: If you check the box to get the Cadillac-branded battery charger, is it too much to ask/expect Cadillac to wire up a quick disconnect plug to the car? Just another detail Cadillac/GM dropped the ball on.

 

[DonD]

Meanwhile I'm just sitting here wondering: If you check the box to get the Cadillac-branded battery charger, is it too much to ask/expect Cadillac to wire up a quick disconnect plug to the car? Just another detail Cadillac/GM dropped the ball on.

I do have a CTEK but at 4.3 max amps, it's more of a maintainer than a charger but it will charge. Don

 

[rubberduck]

The battery will still die when its too old, and will even keep the green lights on the tender while it happens.

I haven't ridden my Harley in the last 6 months (I know.......that is shameful) and after dusting it off and airing up the tires last week - it was dead as a doornail even though its Tender (same one as TallSteve) was green the whole time. It was 3 years old.

The “tender/maintainer” type of units don’t have enough current to restore a deep discharged battery. For that depending on the battery size it may require up to 40A. Batteries are probably the least understood DIY topic. Reading this article is a good start.

https://www.odysseybatteries.com/odyssey/docs/us-ody-tm.pdf

 

[CBH]

Agreed that deep discharging is not a typical automotive use case, so you would expect the battery life to suffer. Trolling motors on boats or golf carts are like this - they exert all their charge while being used since there is not internal source of charge while in use.

I do not believe that is the use case for cars or motorcycles. The battery should be fully charged when returning from usage. Then tenders merely maintain that full charge between uses since cars and bikes charge the battery while the vehicle is in use.

 

[KatyTxCT5V]

I do have a CTEK but at 4.3 max amps, it's more of a maintainer than a charger but it will charge. Don

I have several CTEK chargers from the small 0.8 for my generator to my truck size charger if theirs. They all work fine and if you leave them on longer enough, each has charged and float every battery for me with no issue. Charging a battery is misunderstood sometimes as most people don’t want to wait for the green light / full charge long enough and expect quick results. My 4.3 amp CTEK charges my 5BW usually in about 6 to 7 hrs and then floats every single time. Tenders usually tickle charge with some small voltage on a continuous basis more than float.
I have been traveling and after almost 4 weeks with no charger, my 5BW started / cranked with no issues. You don’t want to charge so fast to generate excessive heat of that will kill the battery. Slower charging is usually recommended by all battery manufacturers.

 

[DonD]

I have several CTEK chargers from the small 0.8 for my generator to my truck size charger if theirs. They all work fine and if you leave them on longer enough, each has charged and float every battery for me with no issue. Charging a battery is misunderstood sometimes as most people don’t want to wait for the green light / full charge long enough and expect quick results. My 4.3 amp CTEK charges my 5BW usually in about 6 to 7 hrs and then floats every single time. Tenders usually tickle charge with some small voltage on a continuous basis more than float.
I have been traveling and after almost 4 was with no charger, my 5BW started / cranked with no issues. You don’t want to charge so fast to generate excessive heat of that will kill the battery. Slower charging is usually recommended by all battery manufacturers.

When I've used my big charger, I almost never use the 45 amp setting, usually use the 15 amp. Don

 

[FLYARMY]

Last winter , I had parked my 5BW in a climate controlled garage from November to early April. ***I also suspend my collision part of my insurance and save a few hundred bucks, while in storage.** When I went to start the car, the battery was dead. Just from sitting a few months , the parasitic electric items in the car , drawn down the battery. When I finally jumped the car, I had a few strange messages on the info display. They went away after a few drives.

 

[DonD]

I've resolved my battery charger issue. Don't have to and don't want to damage the area around the battery itself.

Used a Dremel and was able to carefully trim down the plastic covering the + alligator clamp. now it can securely attach to the positive terminal under the hood.

Tried it briefly on 15 amps. Charger qickly said 95% charge, so I took it off. Don

 

[KatyTxCT5V]

@DonD an easy rule of thumb for safely charging an AGM battery is taking the amp/hr rating (believe a 5BW is 70AH rated, don’t know if a 4BW is the same) and multiplying by 10%. 70x10%=7amps is perfect in this case, but 4.3 works fine and takes a little longer to charge. IMO, charging at 15amps is a little high.

You can charge at a higher amps for quicker results but risk generating excessive internal heat and pressure and could pop the pressure valve making your sealed battery no longer sealed. Then the internal water would evaporate and battery dies.

Normally 10amps is usually mentioned as the maximum recommended charging rate for agm car batteries. Low and slow keeps a battery happy longer.

Of course amps are only one part of the equation, charging voltage is the other. Initial bulk charge between 14.6v to 14.8v improves the agm is getting charged to 100%. Normal battery chargers charging at 14.4v and below will not fully charge an agm battery regardless of a green light or percentage meter showing otherwise. An agm that never gets fully recharged eventually dies sooner than one that does.

I still have the original agm battery in my 2016 C7 Z06 being charged by a 4.3 CTEK. I don’t drive it much and keep it charged. I use a 4.3 CTEK for my 5BW and a 7002 CTEK for my wife’s 2013 FORD Explorer. She’s on her second battery since new. All three are not driven frequently at all.
Our 2022 GMC AT4 gets all the miles and is more frequently driven. Occasionally I’ll put the 7002 CTEK on the AT4 while changing the oil and rotating my tires here at home.

I’m sure others on this forum may have their opinions and methods, but my method has proven to work for me.

BTW- as long as whatever brand charger bring used was designed for agm type batteries, you’re good. I just happen to like CTEK.

Cheers to you and happy Veterans day to those that have served!

 

[DonD]

@DonD an easy rule of thumb for safely charging an AGM battery is taking the amp/hr rating (believe a 5BW is 70AH rated, don’t know if a 4BW is the same) and multiplying by 10%. 70x10%=7amps is perfect in this case, but 4.3 works fine and takes a little longer to charge. IMO, charging at 15amps is a little high.

You can charge at a higher amps for quicker results but risk generating excessive internal heat and pressure and could pop the pressure valve making your sealed battery no longer sealed. Then the internal water would evaporate and battery dies.

Normally 10amps is usually mentioned as the maximum recommended charging rate for agm car batteries. Low and slow keeps a battery happy longer.

Of course amps are only one part of the equation, charging voltage is the other. Initial bulk charge between 14.6v to 14.8v improves the agm is getting charged to 100%. Normal battery chargers charging at 14.4v and below will not fully charge an agm battery regardless of a green light or percentage meter showing otherwise. An agm that never gets fully recharged eventually dies sooner than one that does.

I still have the original agm battery in my 2016 C7 Z06 being charged by a 4.3 CTEK. I don’t drive it much and keep it charged. I use a 4.3 CTEK for my 5BW and a 7002 CTEK for my wife’s 2013 FORD Explorer. She’s on her second battery since new. All three are not driven frequently at all.
Our 2022 GMC AT4 gets all the miles and is more frequently driven. Occasionally I’ll put the 7002 CTEK on the AT4 while changing the oil and rotating my tires here at home.

I’m sure others on this forum may have their opinions and methods, but my method has proven to work for me.

BTW- as long as whatever brand charger bring used was designed for agm type batteries, you’re good. I just happen to like CTEK.

Cheers to you and happy Veterans day to those that have served!

Thanks. The primary reason I bought the CTEK was that they specifically said it could safely charge a battery in the trunk, that the battery didn't need to be removed.

Our other car is a twin turbo 3.3L Kia Stinger. Very big battery and to get it out means not only bending down pretty far but reaching out over the lip of the hatchback. Requires serious effort. Not trying to brag but I'm in good shape despite my years. Accident waiting for a place to happen. Don

 

[rubberduck]

So much misinformation on the internet. An AGM battery will not take more charging current than needed with a proper charger. Because I have a 30A charger does not mean it will put out 30A if the battery doesn’t require that. It will only put out 30A when the battery is in a deep discharge state. I have been using a 30A marine charger for 5 years on my Jeep Odyssey AGM battery. Think for a minute, my alternator can put out 160A.

 

[KatyTxCT5V]

@rubberduck as you stated, with a “proper charger” and I would agree by adding with one that can automatically adjust. Same as a “variable charging” alternator, which is very common on most vehicles nowadays to save fuel efficiency and other claimed benefits. It puts out what is needed.

I still have an older charger that does not vary in amps and would keep putting out the amps that I select until something gives.
The only reason I still keep it around is for the 50amp boost function for jump starting on a rare occasion. Many people still may try to use old chargers or cheap ones that can’t adjust.

I work with various industries in my line of work including battery manufacturers that make all kinds of batteries including agm. So, I doubt my sources would tell me something incorrectly on this subject, since they manufacture the product. I’m not just recycling the internet opinions.

As I stated earlier, there will be various opinions and only stating what I have learned and works for me. Everyone can do whatever they want and it sounds like what you do works for you and what I do works me.

I not trying to start this post with this subject, which has been previously discussed many times on other posts on this forum into a what brand of oil you feel is best…

 

[Tall Steve]

How did you make connections to the battery? There is a very large plastic cover on the positive terminal and no room to remove it. Thanks, Don

Hey Don,

I didn't install the connections, Sewell did it for me as a courtesy when I purchased my BW new..... I just gave them the wire......

My 5BW is 14 months old and no problem with battery/charger system so far...Mine just works like it did on my SS...