Trojan T-105 battery charging tips

[Loafer]

I CHARGED A LAPTOP FOR 1 HOUR AND IT ONLY TOOK 5%!

 

Good news so far! Don't forget to live though, with all this lectric stuff going on!

[WotEver]

 

Yep that's fine, but 50% of what? The 'what' is the bit I want to find out!

Ahh yes, you don't have a SmartGauge... well, you could measure Specific Gravity, or you could measure resting voltage, or... you could always get a SmartGauge ?

[Graham.m]

I CHARGED A LAPTOP FOR 1 HOUR AND IT ONLY TOOK 5%!

 

Which laptop the 2.3 or the 4.5A

[WotEver]

I CHARGED A LAPTOP FOR 1 HOUR AND IT ONLY TOOK 5%!

We're getting there kiddo ?

[WotEver]

I have 4 105s and when I leave the boat they are normally as fully charged as I can get them and then I leave them connected to a couple of solar panels. When I come back to the boat after say a month or more the first 48 hrs the batteries lose voltage more for a given discharge but then buck up again after a couple of charge cycles of 4 hours.

So they get lazy when unused? Seems to agree with what others have stated.

 

Thanks for the helpful input ?

[nicknorman]

Just to mention that at 7A charging current they are still a way off charged. Personally I'd want to get them down to 2.5A at least occasionally. I suspect you could continue to charge at 7A for quite a while in order to get fully charged, because the batteries are currently "lazy". It will get better!

[WotEver]

I was wondering about the 7A. I started writing a post about it but then wondered if it was just a quirk of T105s.

[Graham.m]

I CHARGED A LAPTOP FOR 1 HOUR AND IT ONLY TOOK 5%!

 

So one takes about 4.5A one hour that is 4.5Ahs = 5% on that basis 100% = 90Ahs I think you charged this one

 

The other takes about 2.5A one hour is 2.5Ahs = 5%

[Loafer]

I was wondering about the 7A. I started writing a post about it but then wondered if it was just a quirk of T105s.

 

Don't forget that this was 7A at 15.2V.

 

If he'd reduced his charge voltage down to 14.6, say, then I reckon the tail current would have reduced accordingly. Maybe close to the 100% values? i.e. 1%-3% tail current?

[WotEver]

Yeah, mebbe. I honestly don't know and I'm not going to guess.

[ditchcrawler]

I often see under 2 amps with a voltage of 29.4 volts on a 24 volt system, it takes on my usage around 4-5 hours.

[Loafer]

I often see under 2 amps with a voltage of 29.4 volts on a 24 volt system, it takes on my usage around 4-5 hours.

What bank capacity, d.c.?

[nicknorman]

I was wondering about the 7A. I started writing a post about it but then wondered if it was just a quirk of T105s.

Well put it like this, when I checked ours the other day having been on shore float, put the charger back to bulk at 14.9v and the current for 450AH was 0.5A. That would equate to 0.25A for the Tommy. That is proper charged!

[Loafer]

Well put it like this, when I checked ours the other day having been on shore float, put the charger back to bulk at 14.9v and the current for 450AH was 0.5A. That would equate to 0.25A for the Tommy. That is proper charged!

 

The likes of which my batteries haven't seen since we were last on shore power. Somewhere around mid-2012, I'm thinking!

 

Happy New Year to all the lekky peeps. And also to those who aren't!

[Graham.m]

I have 4 105s and when I leave the boat they are normally as fully charged as I can get them and then I leave them connected to a couple of solar panels. When I come back to the boat after say a month or more the first 48 hrs the batteries lose voltage more for a given discharge but then buck up again after a couple of charge cycles of 4 hours.

 

DC, I am wondering whether the voltage drop you describe is related to stratification of the electrolyte. Surely if the battery has stratification the plates are only partially covered by a full spec electrolyte and thus a smaller area of the plate is available to supply the capacity demanded and there will be a greater voltage drop than expected even though the open circuit voltage of the battery indicates a fully charged battery. If this is the case a quick charge at the maximum voltage for an hour or so should remix the electrolyte and stop/reduce the voltage drop. Or even giving the batteries a good shaking.

 

I seem to remember reading somewhere that a battery left on a float charge is more vulnerable to stratification.

Edited January 1, 2016 by Graham.m

[WotEver]

Well put it like this, when I checked ours the other day having been on shore float, put the charger back to bulk at 14.9v and the current for 450AH was 0.5A. That would equate to 0.25A for the Tommy. That is proper charged!

We come back (well I do) to wondering if there's another load somewhere. Tommy had 7A for two or more hours with it not decreasing.

 

I wish he had a clamp meter.

[Graham.m]

We come back (well I do) to wondering if there's another load somewhere. Tommy had 7A for two or more hours with it not decreasing.

 

I wish he had a clamp meter.

 

I don't think these batteries have ever been fully charged. Taking the gauge reading yesterday of 49% what was the capacity that needed replacing. I think those batteries should have a capacity of >160Ahs working on tthe 49% ( you say it is accurate) they required 80Ahs to full charge. Looking at the charging figures that Tommy posted I cannot see anywhere near 80Ahs going into those batteries yesterday.

 

I don't think Tommy has any stray loads. I suggest that what is needed is to check the battery's SG it will give a very good idea of state of charge and if Tommy gives us the SG reading and approx temp we can work out the temp corrected figures. That needs a £10 hydrometer from a local motor factors etc and will tell Tommy and us what the batteries are saying not guesses.

 

My ball park guess is at end of charging yesterday is a SoC of < 80%

[nicknorman]

We come back (well I do) to wondering if there's another load somewhere. Tommy had 7A for two or more hours with it not decreasing.

I wish he had a clamp meter.

Either that or there's a bit of sulphation and it just needs a proper charge. Just to add that although 15.1v sounds quite high, it is cold at the moment and if the batteries are near ambient temperature say at 5C the effective charge voltage is only around 14.65v so I wouldn't expect much gassing. Of course we don't actually know if the batteries are in a heated cabin or a cold engine bay.

[Dinz]

Daft question?

You are disconnecting the chargers as well as the laptops?

[WotEver]

Either that or there's a bit of sulphation and it just needs a proper charge. Just to add that although 15.1v sounds quite high, it is cold at the moment and if the batteries are near ambient temperature say at 5C the effective charge voltage is only around 14.65v so I wouldn't expect much gassing. Of course we don't actually know if the batteries are in a heated cabin or a cold engine bay.

Yup, all good points but I'm still surprised that the 7A wasn't showing any signs of decreasing. I suspect that the Sulphation is actually pretty hard at present and it'll take a while to shift. Perhaps this is why both you and Loafer found it took a while for your T105s to find their full capacity; the Sulphation took some shifting.

[Graham.m]

Yup, all good points but I'm still surprised that the 7A wasn't showing any signs of decreasing. I suspect that the Sulphation is actually pretty hard at present and it'll take a while to shift. Perhaps this is why both you and Loafer found it took a while for your T105s to find their full capacity; the Sulphation took some shifting.

 

 

As I understand it T105s are supplied with 70% capacity and it is over the next 75 or so cycles that the rest of the battery capacity is formed, So maybe the T105 is not a good choice for boats with limited charging capacity from a suitcase style generator.

[bizzard]

 

 

As I understand it T105s are supplied with 70% capacity and it is over the next 75 or so cycles that the rest of the battery capacity is formed, So maybe the T105 is not a good choice for boats with limited charging capacity from a suitcase style generator.

A bit like Duracell claiming that their batteries are the best and last longest. I've noticed in torches that Duracell batteries give off a slightly dimmer light from new than other makes of dry batteries, so eaking out the power I suppose to make em last longer, crafty.

I charged my 5 year old cheapo leisure battery yesterday up to 15.1 volt and then 13.6v float for a few hours and then switched the charger off, read in bed for an hour with LED light, been out this morning, used pump to fill the kettle for tea. I've got nothing on at the moment and the battery is still holding steady at 12.9 volts after all that time.

[Graham.m]

A bit like Duracell claiming that their batteries are the best and last longest. I've noticed in torches that Duracell batteries give off a slightly dimmer light from new than other makes of dry batteries, so eaking out the power I suppose to make em last longer, crafty.

I charged my 5 year old cheapo leisure battery yesterday up to 15.1 volt and then 13.6v float for a few hours and then switched the charger off, read in bed for an hour with LED light, been out this morning, used pump to fill the kettle for tea. I've got nothing on at the moment and the battery is still holding steady at 12.9 volts after all that time.

 

Yep it seems to be a bit like that, rather than forming the battery fully seems they leave the customer to pick up the cost and form last last bit themselves. Could be that is why they are the cheapest on the market.

 

Buying batteries big enough so usage is around 25% and then it is all in the looking after charging fully and not hammering them too much.

Edited January 1, 2016 by Graham.m

[MtB]

 

 

As I understand it T105s are supplied with 70% capacity and it is over the next 75 or so cycles that the rest of the battery capacity is formed, So maybe the T105 is not a good choice for boats with limited charging capacity from a suitcase style generator.

 

 

That sounds to me as a plumber, rather unlikely. How can that happen?

[Graham.m]

 

 

That sounds to me as a plumber, rather unlikely. How can that happen?

 

That is how they are supplied