telcom battery bank

[pianotuna]

Hi all,

This winter I was not home. There was an early heavy snow and the solar panels on the rv were covered all winter.

So far I've had about 19 amps going into them for one hour. After 24 hours, resting voltage was 8.1

I did another 20 minutes and voltage while charging started at 10.1 and ended at 11.3.

I'm hoping that when I have some shore power, I'll be able to rescue the telcom jars.

[pianotuna]

all four strapped together do 1000 amps.

They have now been in use for 6 years by me.

My biggest load is the microwave at about 170 amps.

I did not measure draw when they were "new to me". These are pulls from cell phone towers, so I have no idea what their oem could manage.

[StirCrazy]

pianotuna wrote:
Hi all,

I got a chance to load test the battery bank.

one set (each 139 amp-hours) was doing 350 amps

the other pair did 550 amps.

I think it is safe to say they survived.

sounds like one didn't do as good eh. What should they pull new?

[MrWizard]

Good news indeed, is the second pair a higher capacity rating than the first pair, 550 to 350 is a big difference, if all 4 are the same rating and same age, then the first pair is not in the same condition as the second pair, but not a total loss

[pianotuna]

Hi all,

I got a chance to load test the battery bank.

one set (each 139 amp-hours) was doing 350 amps

the other pair did 550 amps.

I think it is safe to say they survived.

[theoldwizard1]

pianotuna wrote:
Hi all,
... I'll be able to rescue the telcom jars.

Some telecom jars were about 4' tall !

[MEXICOWANDERER]

If anyone tries to gmail email me remember I've been blocked out since October. Use the message system here.

[MEXICOWANDERER]

https://www.business-humanrights.org/en/latest-news/mexico-worlds-largest-lithium-reserves-set-to-be...

[StirCrazy]

MEXICOWANDERER wrote:


Until LTH starts making lithium batteries here in México I am leery of going automotive size lithium. For solar the Tesla wall pack looks entirely legit. I need more factual info.

Canada just won the bidding war for VW to build their new battery plant in Ontario. does Mexico have any Li mines? that's where the plants are going to be built, close to the natural Resorces and the automotive industry.

the tesla wall is legit, but man is it expensive. I am getting quotes right now to do solar on my house, but I had to pass on the tesla solar wall.

[MEXICOWANDERER]

I've yet to stumble across a conversation that mentions which brand of lithium battery is a standout; survival or cycle wise. That might have to do with the actual weight of each module. It would be hard for me to swallow "a cell is a cell" when it comes to lithium. Unlike western economies I am unable to dig up much information on the subject of China and lithium battery manufacturers. The small experience I have with another type of lithium. Battery is rather sour.

Replacement batteries like for my ereaders use reclaimed cells. Lifespan is less than half of a new battery. The sales pitch though is outright fraud. Keep in mind this is a different type of lithium battery to begin with.

Until LTH starts making lithium batteries here in México I am leery of going automotive size lithium. For solar the Tesla wall pack looks entirely legit. I need more factual info.

[pianotuna]

Hi Mex,

I do have a regular transformer rectifier Battery Charger. I wanted a variac before I got the autoformer.

If I were to yin yang I'd go for Sio2. The problem is my age.

The existing jars don't owe me a dime.

I will ask my cousin to load test them later this month--and will base my decision on the outcome.

[MEXICOWANDERER]

The usual scenario for telecom site batteries is design for long float life with perhaps a dozen or so major discharges. But long term survival at low voltages isn't in their job description.

Paying up the yangying for a lifeline means getting incredibly thick plates. Controlled overcharging sheds substantial amounts of plate material. But if they're super thick it's like having a checking account overdraft protection plan.

But the chances of survival for a battery with lesser thickness plates is less.float maintenance for 10 years will consume a chunk of plate layer as well.

By the way Don if you ever get your hands on a regular transformer rectifier battery charger you can throttle it with your variac. A Fred Flintstone grade sort of adjustable charger.

[pianotuna]

I'm pretty sure I have reduced capacity. But then, I have (blush), turned into a power pole princess. I do love my load support and since I've had the Magnum inverter I've blown one breaker in 7 years (4 of which were as full time).

I'll most probably limp through this year with the telcoms.

I'm on a 23 day trip with 15 stops and all of them have atleast a 15 amp service. Some have multiple 15 amps and my destination has a weak 50 amp.

[MEXICOWANDERER]

I haven't performed a standardized ampere hour test but I did do this...

Let it sit as I described. Then operated a tube heated 24 volt heated reservoir ResMed BiPap for 17 hours (total) via a 300 watt Samlex PSW inverter, disconnected everything then it sat for (perhaps) 4 days.

Observed voltage 12.69

Keep in mind this battery was picked up March 2012 and stood standby for many years being maintained at strictly observed Concorde float values

Conclusion: like me the battery is obsolete so formal testing would be moot. I mentioned this merely as being curious. There is no reason to be prejudiced by assumption. Until I can walk again or have motive assistance I seem to be "stuck" in an environment that has near infallible electrical service. My neighbor across the street is a regional bigwig for CFE the government electricity agency 😄

[StirCrazy]

MEXICOWANDERER wrote:
A few months ago I posted a note about recovering a 11 year old neglected Lifeline AGM. To make a short story shorter, I ended up leaving the battery connected at 15.5 volts for two weeks.

No it didn't heat up
It did not lose 1 gram of weight
But yes, it finished holding 13.3 volts @ 55° for a week afterwards.

Neglected? Yes. Disconnected for 3 years

Was the capacity affected at all? I have revived car batteries before that were DOA some worked with a lower capacity, most didn't... I know that agm can handle a bit more punishment than regular ones, but not a lot more