16.8V charger for equalising Trojans?

[Dr Bob]

10 minutes ago, Richard10002 said:

If 16.8V isn’t available, the Victron with 16.2V may be a good one to go for. I like the idea of sitting in my fat backside in the lounge, and setting or resetting the mode via Bluetooth.

 

....but as Sea Dog said, on the IP22 Bluesmart, the bluetooth doesnt reach to the front of the boat. Ours will be the same so I will have to resign myself to equalising whilst in bed!

[Richard10002]

59 minutes ago, Dr Bob said:

....but as Sea Dog said, on the IP22 Bluesmart, the bluetooth doesnt reach to the front of the boat. Ours will be the same so I will have to resign myself to equalising whilst in bed!

I’m only 45ft, so from the sofa in the lounge to the charger location would be about 24ft with no barriers to a signal, so should work OK. I’ll test things with a Bluetooth speaker and report back

[Sea Dog]

1 hour ago, Richard10002 said:

 

If 16.8V isn’t available, the Victron with 16.2V may be a good one to go for. I like the idea of sitting in my fat backside in the lounge, and setting or resetting the mode via Bluetooth.

At the moment, once in absorption, I have to set an alarm for an hour, then get up and turn the charger on and off, otherwise I can find it’s been on trickle for a few hours, despite the batteries only being partly charged.

The Victron will do 16.2v in normal, but selecting high will give 16.5v if you need more.

Depending on your charger position and boat fit out, you might get a bit more Bluetooth range than I do, but I get about 30-odd feet at a guess. You may be doing it from your bed as Dr Bob suggests, but the good news is you can also select a silent night mode which will self cancel after 8 hours, so you can re-select it if you fancy a lie in! (I've yet to hear mine be anything but silent anyway).

I posted on how the IP22 handles absorption in an earlier post for Dr Bob iirc (maybe on another thread), but if you haven't seen that (or can't find it) and need it, I'll post it again for you.

Edited December 24, 2017 by Sea Dog
Changed 30 of feet back to 30-odd feet!

[Dr Bob]

46 minutes ago, Richard10002 said:

I’m only 45ft, so from the sofa in the lounge to the charger location would be about 24ft with no barriers to a signal, so should work OK. I’ll test things with a Bluetooth speaker and report back

I'm only 6' 2".

[Sea Dog]

9 minutes ago, Dr Bob said:

I'm only 6' 2".

In which case, you'll be fine should you ever buy some Bluetooth boots.

[WotEver]

2 hours ago, Sea Dog said:

In which case, you'll be fine should you ever buy some Bluetooth boots.

These boots are made for talking,

That’s just what they’ll do. 

One of these days these boots

Are gonna talk all over you. 

[Sea Dog]

50 minutes ago, WotEver said:

These boots are made for talking,

That’s just what they’ll do. 

One of these days these boots

Are gonna talk all over you. 

One possibility, though not very stealthy and a bit 1960s.  Another, a bit 70s mind you, might be electric boots with a mohair suit (I read it in a magazine). 

[WotEver]

2 minutes ago, Sea Dog said:

One possibility, though not very stealthy and a bit 1960s.  Another, a bit 70s mind you, might be electric boots with a mohair suit (I read it in a magazine). 

While walking down a yellow brick road. 

[smileypete]

8 hours ago, WotEver said:

Most (all?) of their published optimum charge profiles show a quite steep rise in charge voltage for the last few percent, which is something that I have never seen available in any charger, marine or otherwise. 

Some programmable industrial chargers do (IUIUo). The same can be done with a bench type supply or programmable solar controller in parallel with the usual charger.

US Battery recommend a C/30 limit for finishing charge so we're looking at about 15A for a 450Ah bank which isn't too bad.

[MtB]

So this concept of a 'finishing charge' at elevated voltage is not just a Trojan thing then? 

How do Trojan, US Battery etc expect this ti be done given chargers don't do it? DO golf cart chargers do it perhaps? Has anyone here actually asked Trojan how or where to get a finishing charge of 16.8v at 5 degrees C?

[WotEver]

49 minutes ago, Mike the Boilerman said:

So this concept of a 'finishing charge' at elevated voltage is not just a Trojan thing then? 

How do Trojan, US Battery etc expect this ti be done given chargers don't do it? DO golf cart chargers do it perhaps? Has anyone here actually asked Trojan how or where to get a finishing charge of 16.8v at 5 degrees C?

Looks like this product would do you but I have no idea of the cost. I’m sure it won’t be cheap. It’s a little too large too.

http://www.zivanusa.com/NG1BatteryCharger.htm

They explain how they follow the manufacturers’ curves here...

http://www.zivanusa.com/ChargeCurve.htm

Edited December 24, 2017 by WotEver

[WotEver]

Ahh, they do a 15A one too:

http://www.zivanusa.com/BC1BatteryCharger.htm

450€ so probably around £400

http://kartmasters.fr/shop/en/other-lead-chargers/1103-chargeur-zivan-bc1.html

[smileypete]

3 hours ago, Mike the Boilerman said:

So this concept of a 'finishing charge' at elevated voltage is not just a Trojan thing then? 

How do Trojan, US Battery etc expect this ti be done given chargers don't do it? DO golf cart chargers do it perhaps? Has anyone here actually asked Trojan how or where to get a finishing charge of 16.8v at 5 degrees C?

Unfortunately the narrowboat market is miniscule compared to other markets these things are developed for.

ISTR Victron Combis can have the charge voltage set as high as 16V, not sure whether temp compensation would take it higher.

If it's not possible to provide the necessary voltage for EQ charging, then it would be best to stick to 'Plan A' type batteries I s'pose.

There's some discussion of the charging needed for Trojan type batts over on the ybw forum:

http://www.ybw.com/forums/showthread.php?228458-battery-equalisation-charge

BTW Happy Christmas everyone!

[WotEver]

2 hours ago, smileypete said:

There's some discussion of the charging needed for Trojan type batts over on the ybw forum:

http://www.ybw.com/forums/showthread.php?228458-battery-equalisation-charge

Interesting that nothing’s really changed in the nearly 8 years since that thread ran. Same questions being asked with much the same answers as then. 

[cuthound]

Way back in my career, all changing was done manually. Current limited to the 10 hour rate (to minimise stresses onn the plates)until the voltage reached 2.67 volts per cell (same as 16.0 volts for a volt battery) at 25°C.

[nicknorman]

Can you explain precisely where the “stresses on the plates” arises from? It’s not that I am disputing its existence, it’s just that I’d like to understand the mechanism.

[cuthound]

4 hours ago, nicknorman said:

Can you explain precisely where the “stresses on the plates” arises from? It’s not that I am disputing its existence, it’s just that I’d like to understand the mechanism.

Large currents (charge or discharge) can reputedly cause the plates to distort although I have never observed this and definately cause shedding of the active material.

From the point of the humble technician actually charging the batteries,  charging at the 10 hour rate was a good source of overtime 

 

[smileypete]

5 hours ago, nicknorman said:

Can you explain precisely where the “stresses on the plates” arises from? It’s not that I am disputing its existence, it’s just that I’d like to understand the mechanism.

I don't think it does.

As long as the charge current is limited for the finishing charge stage, then any plate shedding should be kept to an acceptable very low level.

There's quite a bit of info on the web about it, including from battery manufacturers.

[smileypete]

21 hours ago, WotEver said:

Ahh, they do a 15A one too:

http://www.zivanusa.com/BC1BatteryCharger.htm

450€ so probably around £400

http://kartmasters.fr/shop/en/other-lead-chargers/1103-chargeur-zivan-bc1.html

A search for IUIU chargers gets a few more results, eg:

http://www.whisperpower.com/uk/4/13/119/products/battery-chargers/wbc-handy-150-(12v-15a).html

A helpful alternative to reduce the need for separate EQ charging but not essential as I understand it.

[nicknorman]

17 minutes ago, smileypete said:

I don't think it does.

As long as the charge current is limited for the finishing charge stage, then any plate shedding should be kept to an acceptable very low level.

There's quite a bit of info on the web about it, including from battery manufacturers.

Manufacturers disagree with you. Trojan, for example, recommend a maximum of 13% capacity as charging current. Why keep this so far below what the batteries can actually take?

[WotEver]

16 minutes ago, nicknorman said:

Manufacturers disagree with you. Trojan, for example, recommend a maximum of 13% capacity as charging current. Why keep this so far below what the batteries can actually take?

Trojan say somewhere (I’ve read it recently but can’t recall where) that it causes the paste to ‘soften’ and fall off. It also causes heat which in theory at least will cause the plates to move around, exacerbating the effect. 

[nicknorman]

2 minutes ago, WotEver said:

Trojan say somewhere (I’ve read it recently but can’t recall where) that it causes the paste to ‘soften’ and fall off. It also causes heat which in theory at least will cause the plates to move around, exacerbating the effect. 

I don’t really buy the heat thing. The plates are in intimate contact with the electrolyte which has a fairly high specific heat capacity, and I never see any rise in electrolyte temperature associated with fast charge rates.

[WotEver]

19 minutes ago, nicknorman said:

I don’t really buy the heat thing. The plates are in intimate contact with the electrolyte which has a fairly high specific heat capacity, and I never see any rise in electrolyte temperature associated with fast charge rates.

Then I guess it’s just the softening thing. 

I’ve seen plenty of cut open Batteries with buckled plates but maybe that was from too-fast discharges rather than too-fast charges. 

Edited December 25, 2017 by WotEver

[WotEver]

Maybe Trojan’s advice is aimed at limiting surface charge and keeping the charge source <13% achieves this?

An email to their tech support would probably clear it up. They were quick with their reply when I was asking them about charging frequency, if you recall. 

[smileypete]

2 hours ago, nicknorman said:

Manufacturers disagree with you. Trojan, for example, recommend a maximum of 13% capacity as charging current. Why keep this so far below what the batteries can actually take?

I was talking about finishing charge which is an extra step beyond absorption charge.

Why not ask Trojan and see what they say?