A Battery Question

[skyriver]

Originally Posted by CartsRFun

Forgot to say I have the Lester Summit 2 650 watt charger and use the app.

I'm using the 1050 watt version, but when using the CR-260 on either the 650 or the 1050 watt versions you'll need to use the Lester app and change the profiles settings from CR-235/CR-260 to CR-260/CR-450.

Lester makes a mighty fine charger, I've got a new 650 still in the box that I've never used.

[JohnnieB]

Originally Posted by skyriver

So far I'm not very happy with them, at least compared to Trojans. They've been in the Ellis battery service shop where I purchased them for the last couple of days, but they say they can't find anything wrong with them.

Hydrometer readings are good and they charge up well, but when the surface charge is gone they're down to 50.45 on the volt meter. 50.45 divided by 8 is 6.3062 so when compared the Trojan charge scale of 6.37 they're only holding a 90% charge, after paying $1300 for them I expected better.

They're telling me that they are at 100% charge and I'm not happy. A good strong 48 volt pack would settle at 51 volts. I also purchased 8 CR-235's from them for my other cart about the same time and they're good holding at 51 volts.

At-rest voltage for 100% SoC depends on the manufacturer of the battery and the SoC voltages are composite averages of the models within each brand, so they are approximate rather than specific.
Crown = 50.40V
Trojan = 50.93V
US Battery = 51.29V

Attached are SoC charts I've put together for Crown, Trojan and US Battery from the data I've been able to find for them.

Also attached is the source documents the Crown SoC chart is based on. As you can see, some interpolation had to be used.
The source documents for Trojan and US Battery were already delineated in 10% increments.

[CartsRFun]

Skyriver Thank you kindly for your response. Sorry to hear of your plight with the Crowns.

When I purchased my Star Sirius when I told my dealer I wanted maint. free
agm he recommended Crown because of their 3 year warranty. So the Crown 6crv 220ah were ordered and installed on my Sirius.

At first my cart was very quick with strong acceleration to 23-24mph then taper to 25. Over time (4mo) cart would go fast then slooow way down.

So upon finding out that Crown does have a 6crvh 260 ah agm I ordered them with the idea of increasing my run times. Hopefully h means heavier duty.

My cart comes with a 350 ah Curtiss controller and 48v 5.4 hp ac motor.
(supposedly more efficient).

My Lester app has shown a high of 69v during phase 2 charge and 58.8 final charge but now more typically 54.5v.

The Lester profile setting for agm is 22259 and is currently set to 22259.

Initially the charger would dv/dt terminate charging...now the charger stays on
a phase 3 54.5v 1-2amps never shutting off even after 3-4 days.

JohnnieB
thank you kindly for adding in the voltage soc charts.
Wonder what those would be for the Crown 6v agms?

Not my intent to derail your post Skyriver...just hungry to know about
your experiences and my own ..might could help others.

Thank you again

[ThreeCW]

Originally Posted by JohnnieB

At-rest voltage for 100% SoC depends on the manufacturer of the battery and the SoC voltages are composite averages of the models within each brand, so they are approximate rather than specific.
Crown = 50.40V
Trojan = 50.93V
US Battery = 51.29V

Yes, there does seem to be a voltage variance between battery models for the the stabilized voltage at 100% state of charge. For example, my 1 year old Trojan T-125's (240 amp-hr) pack voltages typically look something like this:
18 hrs after charge = 52.18 v
36 hrs after charge = 52.06 v
120 hrs (5 days) after charge = 51.87 v.
Note that these are considerably higher than the 50.93 volts that Trojan publishes.

I kind of wonder if my batteries were filled with a higher strength acid , which is "supposed to" result in more power but a shorter life due to more corrosion effects . If I had a choice, I would rather have a longer battery life.

Skyriver - I wonder if you are seeing just the "normal" voltage variance between battery models as JohnnieB has suggested. The 50.45 stabilized volts you are seeing is pretty much bang on the 50.40 volt Crown number that JohnnieB presented.

[cgtech]

Also of note, AGM & Gel batteries have slightly different voltage readings than FLA, and important differences in charging needs. FLA batteries benefit from occasional over charge (called Equalization charge), but, Equalization is a death sentence for AGM & Gel. The reason is that the electrolyte lost during Equalization can be replaced in a FLA battery, however it cannot in AGM & Gel batteries.

[JohnnieB]

Originally Posted by CartsRFun

When I purchased my Star Sirius when I told my dealer I wanted maint. free
agm he recommended Crown because of their 3 year warranty. So the Crown 6crv 220ah were ordered and installed on my Sirius.

At first my cart was very quick with strong acceleration to 23-24mph then taper to 25. Over time (4mo) cart would go fast then slooow way down.

So upon finding out that Crown does have a 6crvh 260 ah agm I ordered them with the idea of increasing my run times. Hopefully h means heavier duty.

My cart comes with a 350 ah Curtiss controller and 48v 5.4 hp ac motor.
(supposedly more efficient).

My Lester app has shown a high of 69v during phase 2 charge and 58.8 final charge but now more typically 54.5v.

The Lester profile setting for agm is 22259 and is currently set to 22259.

Initially the charger would dv/dt terminate charging...now the charger stays on
a phase 3 54.5v 1-2amps never shutting off even after 3-4 days.

JohnnieB
thank you kindly for adding in the voltage soc charts.
Wonder what those would be for the Crown 6v agms?

69V sounds a bit high for AGM batteries. I don't have any data for Crown AGM batteries but the attached Trojan SoC data for FLA, AGM and Gel, shows quite a drop in max voltages for AGM and Gel. I'd contact Crown for confirmation if 69V is an acceptable value.

Also looks like max charging voltages is lower for AGM than FLA, but 100% SoC is higher.

[JohnnieB]

Originally Posted by ThreeCW

Yes, there does seem to be a voltage variance between battery models for the the stabilized voltage at 100% state of charge. For example, my 1 year old Trojan T-125's (240 amp-hr) pack voltages typically look something like this:
18 hrs after charge = 52.18 v
36 hrs after charge = 52.06 v
120 hrs (5 days) after charge = 51.87 v.
Note that these are considerably higher than the 50.93 volts that Trojan publishes.

I kind of wonder if my batteries were filled with a higher strength acid , which is "supposed to" result in more power but a shorter life due to more corrosion effects . If I had a choice, I would rather have a longer battery life.

Not only is there variations in models within the same make, there are variations within the same model. That is why it is better to get batteries with same date code. Ideally, it would be best to get a set of batteries that were produced sequentially on the same production line during the same work period.

--------------
If you run the fluid level a bit lower than what it started out at when filled on the assembly line, the acid concentration would be bit higher. Also, sulfuric acid is hydroscopic, so it sucks moisture out of the air and a fresh open container might be a bit stronger.

[CartsRFun]

Thank you so much cgtech and Johnnieb for adding in your information.
Very insightful .

Yes come monday I will call Crown battery and inquire as you suggested.
As well as an soc chart for my agms...as well as Lester electonics see what
I can find out

Will post my findings.

I do not wish to deviate or "hijack" skyriver's post...I posted on it because of his new Crown cr 260 flas trying to glean further insight.

May I post my findings here, or elsewhere...if so where?

Thank you everyone!!!!!

[skyriver]

Originally Posted by CartsRFun

Thank you so much cgtech and Johnnieb for adding in your information.
Very insightful .

Yes come monday I will call Crown battery and inquire as you suggested.
As well as an soc chart for my agms...as well as Lester electonics see what
I can find out

Will post my findings.

I do not wish to deviate or "hijack" skyriver's post...I posted on it because of his new Crown cr 260 flas trying to glean further insight.

May I post my findings here, or elsewhere...if so where?

Thank you everyone!!!!!

Absolutely, post here all you want. You're not hijacking. Great information coming in.

[skyriver]

Originally Posted by JohnnieB

At-rest voltage for 100% SoC depends on the manufacturer of the battery and the SoC voltages are composite averages of the models within each brand, so they are approximate rather than specific.
Crown = 50.40V
Trojan = 50.93V
US Battery = 51.29V

Attached are SoC charts I've put together for Crown, Trojan and US Battery from the data I've been able to find for them.

Also attached is the source documents the Crown SoC chart is based on. As you can see, some interpolation had to be used.
The source documents for Trojan and US Battery were already delineated in 10% increments.

Thanks JohnnieB, I had no idea that there was a difference. I just assumed that 50.93 was universal. I drove down and picked them up this morning and I'm delightfully surprised.

They had them for 2 days and I don't know what they did, but after taking the cart for a ride, using the inverter to pump some water, cut some lumber with a skill saw and saw zaw the pack is still holding at 51 volts after 5 hrs.

I'm a happy camper.