Charging Batteries

[Jon Nazareth]

When charging batteries with an Axtronics Smart Charger, the green light comes on after a very short charge and then, they do not hold their power.  Does this mean that the batteries are US?

On the subject of batteries, how often should they be charged if they are simply not being used?  Are there some rules to follow if the condition of the batteries is to maintained?

In both cases, I am talking about Strickalite NiMH batteries.

I am quite ignorant when it comes to volts and amps and rely on the 'just plug it in' method.

Jon

[John Candy]

Jon,
How old are the batteries and what rating are they? Most of those I have bought from Strikalite are either 2100 or 2300 mAh.

Are they Low Self Discharge type ("LSD") in which case they should be OK going for 6 months to a year between re-charging? Strikalite have been supplying LSD type as the norm for several years BUT when I looked a month or so ago, they were saying that LSD type were unavailable (Chinese factory closed) and they were supplying type which were not LSD.

I bought (from a Dutch website) tagged Panasonic Eneloop LSD type (marked made in Japan) instead.

If batteries are NOT "LSD",then I would recommend re-charging every three months.....BUT whatever type they may be, ALWAYS re-charge after use.

John.

P.S. The Axtronic chargers come in two versions, the smaller one is for 2 to 12 cells (2.4 to 14.4V)and the larger covers 12 to 20cells (14.4V to 24V).

[Chris_P]

Strikalite have a good reputation for model battery supply with many specialised packs for garden railway use. Their website also includes details of a refurbishment service so I suggest contacting them direct. https://www.strikalite.co.uk/index.asp

Unfortunately the days of simplicity are long gone with different battery physical and chemical properties requiring more complicated charging and maintenance creating plenty of opportunity for errors.  Some modern battery types are also prone to creating fires if incorrectly charged so compatibility of chargers and battery is also critical to avoid any heat generated during charging harming precious models.  Having had a lucky escape with an LGB loco some time ago very much a case of once bitten twice shy.

[Jon Nazareth]

John/Chris

The batteries were bought in 2014, once used to test the loco and then, never used again until I tried to charge them.

The batteries are NiMH 2.3Ah Low Self Discharge and the charger is for 2.4 - 14.4V Ni-MH/Ni-Cd battery pack.

Looking at the above, it would seem that the batteries have had it.  With regards to the refurbishment service, once the postage has been added, both ways, it may not be worth the outlay.

Had another look at the batteries and charger.  It states on the batteries that they should be charged at 120 mA for 15 hours.  On the back of the charger it states that the Charge Current:Constant 500 mA.  Is the charger 'charge current' too high? 

Jon

[John Candy]

Jon,

The Axtronics charger will not damage the batteries..... I have both types and have been using them for as long as I have been building G3 locos.
I still have battery packs from Strikalite which are 10 years old (and non-LSD type) which are still serviceable.
I have only ever had one pack cause problems and that was caused by leakage. The pack exhibited similar characteristics to yours..... gave full charge signal when it was not.
I removed the leaking cell an re-assembled and it is now back in use.
see  http://g3forum.org.uk/index.php/topic,2230.msg14333.html#msg14333

John

[Jon Nazareth]

John
I removed the shrink wrap from the battery pack but could find no damage nor leakage.  Maybe they've gone beyond saving and, I've no means of testing them.  If I did want to try testing, what sort of meter would I need?

Jon

[John Candy]

Jon,
It may be that the charge has gone so low that the "smart" charger will not pick it up.
An ordinary (non-smart) charger may well do so.
Try putting the pack in the airing cupboard (or other warm place....but not too warm....not on boiler or radiator) for a couple of hours and then try charging again. That has worked for me in the past.
The other alternative is to take a fully charged pack of similar voltage and connect in parallel (i.e. positive to positive and negative to negative....as you would do when jump-starting a car) and that may induce sufficient charge to the dead pack to encourage the smart charger.
Regards,
John.