Another lithium query

Why would an engine start battery which has no other loads except starting, after which it is immediately fully recharged by the alternator ever go flat with no warning? Simply wire an isolator switch from the house positive to the load side of the start isolator and negative to the engine if you don't have a common negative busbar so in an emergency it can be connected direct to the starter motor without going through the start battery. BTW you must have low requirements from the house if you are going to rely solely on solar rather than a mix of alternator, mains and solar. If so why do you need such big bank? I appreciate that the large bank will give you a long period before you run out, but solar on its own will be unlikely to keep up with ongoing usage, particularly if you have a fridge.
The lithium batteries say not to use for starting. Does that include using them to boost a low charged battery?

I have to admit to thinking - since non arrival of lithium batteries - using the starter to power the tiller autopilot whilst under engine. My mast is in up in the Forth. Dunbar lifeboat unfortunately already knows me. Very embarrassing to get to know them again.
 
The lithium batteries say not to use for starting. Does that include using them to boost a low charged battery?

I have to admit to thinking - since non arrival of lithium batteries - using the starter to power the tiller autopilot whilst under engine. My mast is in up in the Forth. Dunbar lifeboat unfortunately already knows me. Very embarrassing to get to know them again.
Is this a temporary solution while you motor up to get your mast?
 
You might be right. But I think connecting directly across to a lead acid might be playing with fire. Perhaps literally…?
I doubt it would actually be dangerous. Where I expect it might fall down is that the sudden inrush of current to the flat lead acid would trigger a BMS shutdown.
However I reckon a small lead acid, not too deeply discharged, and maybe connected by a long cable to act as a crude current limiter, might not cause such a spike in current as to overwhelm the lithium. If using a long cable you'd need to ensure it was adequately fused.

I'm NOT suggesting anybody do this, but I'd like to know whether it would work.
 
The lithium batteries say not to use for starting. Does that include using them to boost a low charged battery?

I have to admit to thinking - since non arrival of lithium batteries - using the starter to power the tiller autopilot whilst under engine. My mast is in up in the Forth. Dunbar lifeboat unfortunately already knows me. Very embarrassing to get to know them again.
No reason why you should not run the autopilot off the start battery. Under motor the alternator will more than keep up with the demand. Perhaps one of these as a backup
amazon.co.uk/battery-jump-starter/s?k=battery+jump+starter
 
No reason why you should not run the autopilot off the start battery. Under motor the alternator will more than keep up with the demand. Perhaps one of these as a backup
amazon.co.uk/battery-jump-starter/s?k=battery+jump+starter
I've borrowed a jump starter for the trip. I know it is being very careful, but it's a new battery and you never know ...

I wouldn't need it if Eco-Worthy kept to their promised delivery time, or it was possible to contact them. If I was ordering again (and the batteries seem to be fine) I would go via Amazon who are then responsible for delivery.
 
I've borrowed a jump starter for the trip. I know it is being very careful, but it's a new battery and you never know ...

I wouldn't need it if Eco-Worthy kept to their promised delivery time, or it was possible to contact them. If I was ordering again (and the batteries seem to be fine) I would go via Amazon who are then responsible for delivery.
Ideal opportunity to cancel the order and give some thought to what you actually want/need and if it turns out to be Lithium, buy something better than the ones you have ordered. To be blunt, they are crap, hence the price.
 
Ideal opportunity to cancel the order and give some thought to what you actually want/need and if it turns out to be Lithium, buy something better than the ones you have ordered. To be blunt, they are crap, hence the price.
Perhaps good advice. The reviews of the batteries seemed good, not so much customer service. But why do you think they are so bad? And what would you suggest in their place?
 
Eco-Worthy batteries cancelled on PaulRainbow's advice (I think he knows a bit more than do I).

These were for boat No 2, so only for pottering about the East Coast (fridge, autopilot and not much more). I had 2 off 110ah lead acid batteries and these seemed to do fine and probably offered less than 220ah. Can I get by with 1 off 100ah lithium? Or better with 2 off?

Push me in the direction of a non premium lithium battery.
 
Eco-Worthy batteries cancelled on PaulRainbow's advice (I think he knows a bit more than do I).

These were for boat No 2, so only for pottering about the East Coast (fridge, autopilot and not much more). I had 2 off 110ah lead acid batteries and these seemed to do fine and probably offered less than 220ah. Can I get by with 1 off 100ah lithium? Or better with 2 off?

Push me in the direction of a non premium lithium battery.
You get very nearly double the useful capacity with lithium, with much better charging behaviour. So I think you'll be absolutely fine with only one.
No direct experienced but I gather that Fogstar are well regarded amongst the lower priced batteries.
So long as it has a programme Bluetooth BMS, and doesn't have a totally weedy maximum charge/discharge current, it should do the job.
 
Eco-Worthy batteries cancelled on PaulRainbow's advice (I think he knows a bit more than do I).

These were for boat No 2, so only for pottering about the East Coast (fridge, autopilot and not much more). I had 2 off 110ah lead acid batteries and these seemed to do fine and probably offered less than 220ah. Can I get by with 1 off 100ah lithium? Or better with 2 off?

Push me in the direction of a non premium lithium battery.
I would go with Fogstar, i use their EVE cells for my Lithium installations. I believe their Drift Eco range do not have Bluetooth, in which case i would pay the little extra and get one of the Fogstar Drift ones. Lithium Leisure Battery | Fogstar UK

2 x 110Ah lead acid gives you a usable capacity of 110Ah, when new. 100Ah Lithium gives to a comfortable 80Ah usable capacity.
 
Thanks for the advice. I'll go Fogstar. But as a matter of interest, why is Bluetooth useful? I would be hoping for something you can install and forget, not really being a gadget man.
 
Thanks for the advice. I'll go Fogstar. But as a matter of interest, why is Bluetooth useful? I would be hoping for something you can install and forget, not really being a gadget man.
You can monitor what's going on inside the battery, check everything is as it should be and you can adjust settings. You might not want to change anything, but it's definitely useful to take a look now and again, make sure everything is good.
 
Thanks for the advice. I'll go Fogstar. But as a matter of interest, why is Bluetooth useful? I would be hoping for something you can install and forget, not really being a gadget man.
Without Bluetooth it's just a black box and you have no idea what's going on inside. Even if you don't fiddle with any settings, if you ever have any problems, you've got much more information to go on.
And you may find you do want to change some settings to suit your specific installation.
Finally, if you want to be a bit of a cheapskate, you can check the state of charge via Bluetooth, rather than fitting a proper battery monitor (a monitor will be more accurate, though).
 
I have the Fogstar Drift and can say the Bluetooth is exceptionally useful when doing any wiring because you can turn the battery off internally. It’s still wise to be careful but if the terminals aren’t live then it’s quite reassuring and there are no sparks when connecting. Once wiring is done just turn the battery back on internally the app.
It’s useful for other things, but for a low tech person this feature is worth having.
 
Eco-Worthy batteries cancelled on PaulRainbow's advice (I think he knows a bit more than do I).

These were for boat No 2, so only for pottering about the East Coast (fridge, autopilot and not much more). I had 2 off 110ah lead acid batteries and these seemed to do fine and probably offered less than 220ah. Can I get by with 1 off 100ah lithium? Or better with 2 off?

Push me in the direction of a non premium lithium battery.
I have followed this with interest for my little boat ( other thread ) and decided also to follow pauls advice here if I go lithium.
It will cost me an extra £150 overall for the two batteries over the ones I found, which is worth it for the bluetooth, knowing zI am getting decent quality, ( or thinking it anyway) and getting rid of that nagging feeling that this cheap shit might burn my boat to the waterline :)
So thanks Paul!
 
A positive word about Eco-Worthy. When I finally did make contact with their customer service they cancelled and repaid very speedily.

Another comment: I have just had to buy a new bike battery. £200 for 10ah! As against £300 for 100ah for the boat. Yachting prices are lower than at least one other consumer area.
 
Another comment: I have just had to buy a new bike battery. £200 for 10ah! As against £300 for 100ah for the boat. Yachting prices are lower than at least one other consumer area.
It's a different technology. Bike batteries are usually a more volatile, high performance chemistry. Although I must say £200 for 10Ah does seem a bit much. Was that a genuine branded one, rather than a knock off?

(Not that I'm advocating knock off ebike batteries- there are some horrible stories out there)
 
It's a different technology. Bike batteries are usually a more volatile, high performance chemistry. Although I must say £200 for 10Ah does seem a bit much. Was that a genuine branded one, rather than a knock off?

(Not that I'm advocating knock off ebike batteries- there are some horrible stories out there)
Genuine but not Brompton, if you know what I mean. Woosh aftermarket kit.
 
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