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Blue7
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#85 Many thanks for that explanation Roger Thumb Up

Do you know why a 'normal' battery charger can't be used to charge a Lithium battery?

David 

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I think that normal battery chargers have stages where they pulse at higher voltages. This is needed to maintain lead acid batteries, but definitely unwanted for Li ion ones.

I bought a halfords intelligent charger, and when I set it to 'Li ion' it skips these stages.

Simon

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Blue7
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To update my situation, I received this advice from Jack Webb:

There is a difference in the capacity of the Banner, but the 12ah is the rating in Lithium Amp Hours - not PbEq Amp Hours as every lead acid battery is measured in. The reason for the difference is down to the usable capacity of the battery itself - a LiFePO4 battery has a far superior usable capacity which is typically around double that of lead acid chemistries. 

Jack also suggested fitting a battery isolator switch along the negative lead which looks like an easier task, for me, and I can fit the switch somewhere inside the car, one of these

https://www.12voltplanet.co.uk/battery-isolator-changeover-switches.html

It would certainly save money in electricity costs because the Lithium battery, if isolated, holds its charge over winter and does not require a trickle charge, which I have noticed with my new lawnmower lithium battery.

At some stage I will determine just how long it takes for the immobiliser to cause the lithium battery to go into LVP mode.

To solve the problem with my Halfords jump start unit not operating because it seels the LVP as a dead battery, I have ordered a NOCO Boost Sport GB20 500A jump starter, which has an override switch that allows it to charge a battery that appears to be dead.

 

 

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Isolating the ground will preserve the battery and I have wired things that way in the past but it isn't a recommended way to kill the engine.

Stephen

Democratic dissent is not disloyalty, it is a positive civic duty

Bizzielizzie13
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In reply to Blue7's question/s. 

I fitted the Caterham FIA battery cut-off 'kit' as I had heard that the load imposed by the immobiliser would, as with the Banner cause the battery to go flat over time. It was not an easy job, although help with some info (template etc) from JK certainly did help! Had to do some of this upside down under the dash & in the end I had to remove Speedo & Rev Counter to get access & finding the correct wire for the ignition was not straight forward. It was worth it in the end as it now has a 'proper' cut off for Track-Day use & security. Not to mention that thus far at least, I have not had to charge the battery.   

I've have had a few bits from 12v Planet for our camper & found them very good, but you do get everything you need in the Caterham kit, extended cables etc etc & would vote for it as the way to go.

 

timb2117
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Hi, I have followed this thread keenly, fitted my Lion a short while ago it worked superbly.

After about 2 weeks of no car use it was flat (thank heavens for "in battery" computers that isolate it before it becomes flat dead like a lead acid would've) - I'm guessing the immobiliser.... Nice charge on the NOCO2 and its back to A1.

Sooo - just fitted the FIA switch PURELY to the ground cable from battery (yes I know there are better ways to fit it :) but want utter simplicity for my brain to cope) - which should kill the immobiliser drain.

My Q? is - if I flip the FIA switch to off, and therefore there's no Ground/ circuit could I attach the NOCO 2 and charge it safely without removing the battery cables or do I need to take them both off before charging, like the instructions say.

In anticipation thanks for the know how.  

Blue7
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#97 I have been charging my Lithium battery while it is still connected via the power socket and no problems.

David

Jonathan Kay
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"... fitted my Lion a short while ago it worked superbly."

Which model, please?

Thanks

Jonathan

Jonathan Kay
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"Sooo - just fitted the FIA switch PURELY to the ground cable from battery (yes I know there are better ways to fit it :) but want utter simplicity for my brain to cope) - which should kill the immobiliser drain.

"My Q? is - if I flip the FIA switch to off, and therefore there's no Ground/ circuit could I attach the NOCO 2 and charge it safely without removing the battery cables or do I need to take them both off before charging, like the instructions say."

Is there only the one earth (ground) cable from the battery?

If there is and you've disconnected it with that switch and the conditioning charger is connected directly to the battery then removing any live cables from the battery wouldn't have any further effect.

Jonathan

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Has there been any discussion here about charging LiFePO4 batteries at low temperatures and driving your car at temperatures below 0C?

When I've looked at LiFePO4 batteries for my campervan, they are usually specced to -20C for discharge, but the lower limit is 0C for charging.  If it has an integrated BMS (battery management system), then this may be set to  prevent charging below 0C to protect the battery , but if you drive your car, then the battery's just discharging.  If the BMS doesn't prevent charge below 0C, then you risk damaging your battery.  

Simon