Lithium battery conversion

Trident

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Think your missing the point ,yes you can by tinned lugs but you still need the tools to secure them properly because as you know the cause of fires/burnt cables,melted etc are loose connections especially with some of the amperages on 12v systems
I think you missed where he said :

"You need hydraulic crimping, especially with lithium. The high current potential of lithium will not tolerate high resistance connections. A set of cheap hydraulic jaws is about £35."

Now I would not be happy with cheap ones for £35 as I've professionally replaced lots of bad crimps one by cheap equipment BUT, if you properly check each crimp and are careful and prepared to waste a few lugs if the cheap hydraulic kit doesn't do a perfect job every time then an Amazon set would be fine for home use. The key is to tug test every one and make sure the cable is stripped to the right length etc.
 

gaylord694

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If someone wants to use cheaper components for one reason or another then who are we to criticise yes it's nice to give advice and guidance but ultimately it's there boat so the final decision is there's let them do what ever they like
 

Neeves

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PBO is about members, and readers, conducting tasks that would normally be conducted by 'experts', call them commercial operators.

If tasks, installations, demand certain specific tools or specialised skills and tests (I have heard of Trident's tug test, post 121 - have others?) then we posters are at fault for not underling the risks. The advice is commonly given on the basis the individual basing their actions on that advice is doing so based on their own judgements.

If you read Noelex post, an expert in marine electronics, his complaint is with the lugs, not the crimp tools. To me the 'offer' was for crimpers - the lugs were a freebie.

I'm not concerned at the contradictions - any contradictions need to be aired and checked.

Its the problem with the internet - no peer review - except by the members.

Jonathan
 

geem

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Think your missing the point ,yes you can by tinned lugs but you still need the tools to secure them properly because as you know the cause of fires/burnt cables,melted etc are loose connections especially with some of the amperages on 12v systems
No I am not. Read post 117
 

gaylord694

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PBO is about members, and readers, conducting tasks that would normally be conducted by 'experts', call them commercial operators.

If tasks, installations, demand certain specific tools or specialised skills and tests (I have heard of Trident's tug test, post 121 - have others?) then we posters are at fault for not underling the risks. The advice is commonly given on the basis the individual basing their actions on that advice is doing so based on their own judgements.

If you read Noelex post, an expert in marine electronics, his complaint is with the lugs, not the crimp tools. To me the 'offer' was for crimpers - the lugs were a freebie.

I'm not concerned at the contradictions - any contradictions need to be aired and checked.

Its the problem with the internet - no peer review - except by the members.

Jonathan
Like I say who are we to judge let's hope anyone who is thinking of taking on there own practical tasks albeit plumbing, electrical reads the abundance of information available to them and hope it all goes well for them
 

geem

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I think you missed where he said :

"You need hydraulic crimping, especially with lithium. The high current potential of lithium will not tolerate high resistance connections. A set of cheap hydraulic jaws is about £35."

Now I would not be happy with cheap ones for £35 as I've professionally replaced lots of bad crimps one by cheap equipment BUT, if you properly check each crimp and are careful and prepared to waste a few lugs if the cheap hydraulic kit doesn't do a perfect job every time then an Amazon set would be fine for home use. The key is to tug test every one and make sure the cable is stripped to the right length etc.
The ones I have work fine. I think bad crimps are operator error. Thr hydraulic pressure is huge and the crimps work but the cheap ones are fiddly to use.
For the amount I am doing and the few people I have lent them to they are OK. If I was doing this full-time I would also buy a proffesional quality set
 

Trident

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The ones I have work fine. I think bad crimps are operator error. Thr hydraulic pressure is huge and the crimps work but the cheap ones are fiddly to use.
For the amount I am doing and the few people I have lent them to they are OK. If I was doing this full-time I would also buy a proffesional quality set
Actually the cheap hydraulics are fine - the dies that come with them are regularly a problem

I tested one set after issues in a customer boat and found his 35mm cable needed the 25mm die to make a good joint and his 16mm needed the 10mm die. Even a quite expensive set (IIRC £35 for just two die) of 120mm dies I bought for a "Big" job were unsafe - I could pull every going apart - and I had to bin them and go and find a better set

The moral is as ever , check every thing you do and don't assume that a crimp that looks nice from the fancy looking crimper one has will actually do the job properly
 

Neeves

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Like I say who are we to judge let's hope anyone who is thinking of taking on there own practical tasks albeit plumbing, electrical reads the abundance of information available to them and hope it all goes well for them
By and large - we offer good peer review. But 'things' slip through the net.

It merits saying

There have been a number of threads on lithium installation. The frequency is beginning to dwarf anchor threads :) - rightly so, anchors are simple.

The motivation for Lithium threads (I assume) is to provide background - and encourage others to follow the thread's (or post) authors practice? If the intention is not to encourage - its PBO - why post.

But there are risks and authors (of anchor threads - at least) have a responsibility. Repetiton is good (sorry Norman).

Jonathan
 

PaulRainbow

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If someone wants to use cheaper components for one reason or another then who are we to criticise yes it's nice to give advice and guidance but ultimately it's there boat so the final decision is there's let them do what ever they like
If someone is using inferior methods, tools, or materials then we absolutely should criticise, especially when system integrity and/or safety is concerned.
 
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Sea Change

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Another happy user of £30 hydraulic crimpers here. My system runs over 200A currents on a daily basis, and has been working fine for over two years now.

Yes sometimes I have had to drop a size to ensure a good crimp, but I think that's often down to the quality of the actual lugs.

Size your cables generously, work carefully and methodically, and use contact cleaner prior to making connections.
 

geem

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Actually the cheap hydraulics are fine - the dies that come with them are regularly a problem

I tested one set after issues in a customer boat and found his 35mm cable needed the 25mm die to make a good joint and his 16mm needed the 10mm die. Even a quite expensive set (IIRC £35 for just two die) of 120mm dies I bought for a "Big" job were unsafe - I could pull every going apart - and I had to bin them and go and find a better set

The moral is as ever , check every thing you do and don't assume that a crimp that looks nice from the fancy looking crimper one has will actually do the job properly
I agree. The dies that came with mine had numbering that made no sense. It didn't take long to realise what dies to use for what lugs. Once I had that sussed, the connections were robust but for the unwary, you could get it wrong
 

Bobc

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I agree. The dies that came with mine had numbering that made no sense. It didn't take long to realise what dies to use for what lugs. Once I had that sussed, the connections were robust but for the unwary, you could get it wrong
Same with my one
 

Daverw

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I’m just about to do the final bit of fitting the batteries, all else upgraded over the last two years, using the Chinese crimpers has been fine, just to ask all, the Victron stuff shows battery fuses at puss bars and others show close to batteries? Any comments?
 

Sea Change

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I’m just about to do the final bit of fitting the batteries, all else upgraded over the last two years, using the Chinese crimpers has been fine, just to ask all, the Victron stuff shows battery fuses at puss bars and others show close to batteries? Any comments?
As close to the batteries as possible. ABYC say 7", ok that's not a UK standard but I can't think of any reason to have the fuse any further from the battery than necessary.
 

Sea Change

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I wonder how much it really matters to keep the main +ve and -ve runs the same lengths? LFP has a very flat voltage curve so there will be minimal difference between the batteries unless you are in the top or bottom 5% of SOC, which isn't somewhere your batteries should spend any time.

People have paralleled up vastly different LFP capacities, and in hybrid systems put them together with a different chemistry entirely, and it doesn't seem to cause any problems.

Perhaps the requirement to keep the runs the same length is a hangover from best practice with lead acid?
 

Trident

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As close to the batteries as possible. ABYC say 7", ok that's not a UK standard but I can't think of any reason to have the fuse any further from the battery than necessary.
This

I'm not saying the UK /EU standards are not good but I find the ABYC to be safer and more thorough in its recommendations so always work to that. As close as possible to the batteries always and before the cut off switch
 

Trident

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I wonder how much it really matters to keep the main +ve and -ve runs the same lengths? LFP has a very flat voltage curve so there will be minimal difference between the batteries unless you are in the top or bottom 5% of SOC, which isn't somewhere your batteries should spend any time.

People have paralleled up vastly different LFP capacities, and in hybrid systems put them together with a different chemistry entirely, and it doesn't seem to cause any problems.

Perhaps the requirement to keep the runs the same length is a hangover from best practice with lead acid?
I did on my first LFP build but with my latest with EVE packs I have not bothered. All the negatives are at the same length from all the packs and all the positives are the same length from all the packs (to the mm) but the pos and neg are not the same as each other and it seems to make absolutely no difference to anything . When you think most people have things like a shunt in the neg circuit anyway which either adds length or resistance or has some other minute effect I think its more a broad stroke piece of advice from the old days .
 
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