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Acton launch on Friday AM? (08/28/20)

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3 weeks 3 days ago #10096 by tlainhart
Replied by tlainhart on topic Acton launch on Friday AM? (08/28/20)

guyw wrote: Frank has already responded with the link to my go to recommendation for a battery. Taken care of, it should last many years and is at least twice the battery that you were using.
A good rule of thumb for battery charging is to take the stated capacity and divide by 5 to 10 for the charge rate. So for example, the newly recommended battery is a 5 Ah battery, so a charger that can charge at a 500 ma to 1000 ma rate would be about right. The faster you charge, the more heat generated in the battery as it charges. Heat is an enemy for a battery's longevity.


Thanks Guy. Not knowing any better, I would have gone down the path of Ni-Cad or Ni-Mh, which is what the dead battery is, I think. One advantage to that technology appears to be weight - that lead-acid battery is not light (comparatively).

Googling advantages/disadvantages of NiCad vs. lead-acid seems to be in order. That lead-acid battery is certainly less expensive.

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3 weeks 2 days ago #10098 by guyw
Replied by guyw on topic Acton launch on Friday AM? (08/28/20)
Todd,

After 12hrs on the car charger, the smart charger recognized the battery pack as a real battery. I then ran it through a repair cycle, which completed. Then I ran it through a complete charge cycle. The result is that the charger thinks the battery is charged, and sure enough, it is putting out about 13.6 volts at no load. The key will be if it holds the charge, and what the current capacity is. I will see what I can determine.

Guy.

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3 weeks 2 days ago #10100 by tlainhart
Replied by tlainhart on topic Acton launch on Friday AM? (08/28/20)
Ha - I'm imagining that you have the battery on a gurney, slowly raised to the ceiling while Van de Graaf generators throw lightning - It's Alive!!

I read up on Ni-Cd vs. lead acid batteries some this morning. One advantage of the Ni-Cd is (if I read it right) that it can go dead and still be cycled, which seems that a lead-acid can't do as well. Many more cycles in a Ni-Cd as well. However, discharge, even while just sitting on the shelf, happens pretty quickly with a Ni-Cd, whereas a lead-acid can sit in standby for long periods with no discharge.

Probably bets are off with a 23-year old battery.

That said, I think that Ed has a similar battery that he bought from Pratt, perhaps of the same vintage. I was at an Acton launch with him and he was using it then.

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3 weeks 1 day ago #10102 by tonypv
Replied by tonypv on topic Acton launch on Friday AM? (08/28/20)
I posted some pictures from the launch in the Gallery in Bandit Launches.
The following user(s) said Thank You: tlainhart

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