Eco-Worthy batteries

[GUMPY]

Eco-Worthy has a bit of a sale on.

Thing that caught my eye was the 100Ah batteries

https://uk.eco-worthy.com/products/lifepo4-12v-100ah-lithium-iron-phosphate-battery

Are these a straight drop in for an LA battery ? Would I need to think about the feed from the car alternator? Most charging will just be Victron Solar and Victron Charger.

Edited September 2, 2023 by GUMPY

[churchward]

I think both Victron devices you mention have a Lithium battery setting so should be fine .  The alternator is a different matter and could need a BMS in between. Victron does suitable devices.

 

Victron Lithium Battery Smart BMS CL 12-100 – Onboardenergydirect

 

[GUMPY]

1 hour ago, churchward said:

I think both Victron devices you mention have a Lithium battery setting so should be fine .  The alternator is a different matter and could need a BMS in between. Victron does suitable devices.

 

Victron Lithium Battery Smart BMS CL 12-100 – Onboardenergydirect

 

Starting to get expensive, I could just cut the alternator feed to the battery with a relay in the van when the engine is running. I don't need the charging from the alternator.

[Jen-in-Wellies]

Deleted

[MtB]

3 hours ago, GUMPY said:

Would I need to think about the feed from the car alternator?

 

Yes, if you are using it to replace a LA battery. The mystery BMS inside the LFP battery is highly likely to just disconnect the alternator when it decides any individual cell voltage has risen above what it notionally regards as 'fully charged', leading to hours of fun fitting a new alternator. 

 

 

Until they figure out a solution to this problem, any LFP described as a "drop-in" replacement for a LA is kidding the customers.

 

 

[Jen-in-Wellies]

If you have a lead acid connected to the alternator, then this can remain connected at all times, saving the alternator from a BMS disconnect. Then charge the Lithium from the lead acid via a battery to battery charger like https://www.victronenergy.com/dc-dc-converters/orion-tr-smart-non-isolated

[churchward]

11 minutes ago, Jen-in-Wellies said:

The Victron BMS is marketed specifically for Victron Lithium batteries. If you tried to attach it so some one else, how do you ensure that you have the individual cell voltage monitoring is set up correctly? Their BMS uses a pair of three pin plug/sockets to make these connections, but if/how the pin outs match to the cell junctions isn't given.

I've seen Daly BMS used with success. https://offgridpower.solutions/shop/daly-12v-4s-bms-for-lifepo4-battery

 

Yes other BMS will work as well.  The point is one needs a BMS to stop the alternator being melted.

 

Edited September 2, 2023 by churchward

[MtB]

3 minutes ago, Jen-in-Wellies said:

If you have a lead acid connected to the alternator,

 

Probably not, given the OP asked this:

 

"Are these a straight drop in for an LA battery ?"

 

 

 

 

 

And it seems to be for a van not a boat.

 

 

[Jen-in-Wellies]

11 minutes ago, churchward said:

Yes other BMS will work as well.  The point is one needs a BMS to stop the alternator being melted.

 

The BMS is protecting the battery, not the alternator. You need some other way of protecting the alternator from self destructing when the BMS cuts the connection to and from the Li batt. The Victron BMS is still relying on a lead acid battery in the way I described to prevent this.

A van will still need a starter battery, able to handle high currents to crank the engine over. The drop in Lithium linked to has a maximum of 100A in and out, which isn't sufficient.

[churchward]

10 minutes ago, Jen-in-Wellies said:

The BMS is protecting the battery, not the alternator. You need some other way of protecting the alternator from self destructing when the BMS cuts the connection to and from the Li batt. The Victron BMS is still relying on a lead acid battery in the way I described to prevent this.

A van will still need a starter battery, able to handle high currents to crank the engine over. The drop in Lithium linked to has a maximum of 100A in and out, which isn't sufficient.

That's true to a point and I misread the OP and assumed we were referring to a boat with a LA starter battery and lithium house batteries.

[GUMPY]

Alternator feeds the battery in the car and the battery in the Caravan when towing.

If and its a big if I go ahead with it I will just remove the feed from the alternator to the van battery.

Only reason for changing is to save weight in the caravan.

 

Yes I know shouldn't have asked  on here but I thought I would gain some knowledge from the Hive Mind.

 

The whole thing is further complicated by the fact the car has a smart alternator. 

[BEngo]

If you can do away with the alternator to Li feed the new battery will be a near drop in

 

You will need to adjust the Victron kit settings to suit Li.

 

Smart alternators are not suited to Li batteries unless a B2B charger is added in.

 

N

[Tony Brooks]

6 minutes ago, BEngo said:

Smart alternators are not suited to Li batteries unless a B2B charger is added in.

 

Which is why I think B2Bs were introduced, initially for specialist vehicles like ambulances. As I understand it, it is virtually impossible to fit a conventional advanced controller to smart alternators.

[BEngo]

1 hour ago, Tony Brooks said:

. As I understand it, it is virtually impossible to fit a conventional advanced controller to smart alternators.

This is true.  The smart alternator already has one.  Sometimes it is part of the ECU computer, less often it is in another computer on the vehicle.

 

One of the characteristics of a smart alternator is that it is not programmed to fully charge the battery (s).  It tries to have some charge space left over so as the brakes go on the alternator can be sent to full charge rate to provide some 'regenerative braking'.  Keeping the lead acid battery not fully charged is not really good for it, hence the prevalence of AGM and other starved electrolyte batteries which are a bit less prone to sulphation.

 

OTOH, smart alternators come with connections to the vehicle data bus, so for those who speak CANBUS and have electronic  know how it is possible to make your own controller, as Nicknorman has done.

 

N

[GUMPY]

5 hours ago, BEngo said:

This is true.  The smart alternator already has one.  Sometimes it is part of the ECU computer, less often it is in another computer on the vehicle.

 

One of the characteristics of a smart alternator is that it is not programmed to fully charge the battery (s).  It tries to have some charge space left over so as the brakes go on the alternator can be sent to full charge rate to provide some 'regenerative braking'.  Keeping the lead acid battery not fully charged is not really good for it, hence the prevalence of AGM and other starved electrolyte batteries which are a bit less prone to sulphation.

 

OTOH, smart alternators come with connections to the vehicle data bus, so for those who speak CANBUS and have electronic  know how it is possible to make your own controller, as Nicknorman has done.

 

N

I have been watching what the smart alternator does 🤔

When accelerating it's off at about 12.4v,  when lifting off the accelerator and using overrun the volts go up to 14.7v to aid braking. With the caravan connected it's 14.7v all the time😱

Interestingly if I plug the van in with the engine running it doesn't recognise that it's there, this led on one journey to the ign light coming on as the Fridge had depleted the car battery,  a stop and restart and all was well. This is why I have a volt monitor in the cig socket.