Q for the battery/electrical gurus

Submitted: Wednesday, Feb 24, 2016 at 16:45

ThreadID: 131680 Views:1891 Replies:3 FollowUps:2

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Member - wicket

Could one of you learned posters tell me what the highlighted figures refer to in this battery charging table. thanks

battery chart

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Reply By: Member - Racey - Wednesday, Feb 24, 2016 at 17:01

Wednesday, Feb 24, 2016 at 17:01

The "C" refers to the battery capacity. E.G. 100 amp/hr battery charging current = 100 x 0.3C = 30 amps

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Reply By: Battery Value - Wednesday, Feb 24, 2016 at 21:04

Wednesday, Feb 24, 2016 at 21:04

As has been said, the max allowable bulk charging rate is 0.3C (e.g. 30A for a 100Ah battery).
Once the absorption level of 14.7V has been reached the max time after which the charger should switch back to float is 2 hours.

The rest of it doesn't make sense because these lower float voltages can be applied without time limit.

Where did you find this piece of (mis)information?

cheers

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Follow Up By: Member - wicket - Wednesday, Feb 24, 2016 at 22:50

Wednesday, Feb 24, 2016 at 22:50

This is not (mis) information but rather the charging regime for Lead Crystal batteries, if you aren't conversant with them , they are somewhat new on the scene, then have a read about them here, lots to like about them
http://www.alphaenergy.com.au/Lead-Crystal-Batteries

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Reply By: cruza25 - Thursday, Feb 25, 2016 at 12:37

Thursday, Feb 25, 2016 at 12:37

These could be an interesting new alternative for 2nd battery and camper trailers
A 55a optima yellow cost around $340
A 55a lead crystal around $440
The spec says they can fully discharge without loss of capacity
We need a volunteer to field test them in real life touring use

http://au.rs-online.com/web/p/lead-acid-rechargeable-batteries/8262758/

Spec sheet

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Follow Up By: HKB Electronics - Thursday, Feb 25, 2016 at 13:46

Thursday, Feb 25, 2016 at 13:46

Are you talking about the Optima or lead crystal?

The specs for the lead crystal show:
Greater Cyclic Life - 6000 cycles to 20%, over 1600 to 80% DOD
that indicates they suffer from over discharge like any other battery.

It has been circulated that Optima's can be discharged to zero without
harm but the company won't provide a life versus DOD stating that it is
commercially senstive information!

The last I read on Optimas was:
1200 cycles to 0% SoC ( 10.5v ) and 2,000 to 20% SoC ( 11.58v )
so Optimas also suffer the same as any other battery if severly discharged
similar to the above.

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