OK that's fair, makes sense. I'm an amateur at this van business so learning as I go - which is why I find this forum and the community on it a great help.
Leisure Battery - accidentally drained, what next?
- Thread starter interbear
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OK that's fair, makes sense. I'm an amateur at this van business so learning as I go - which is why I find this forum and the community on it a great help.
Good point @MK2Golf24v about turning fridge on. It will run continuously until reaches set temperature. This will use more power than when it's at set temperature and normal cycling to maintain temperature.
Also make sure to have something in fridge. Eg bottles or such. Empty fridge is harder to cool.
Also make sure to have something in fridge. Eg bottles or such. Empty fridge is harder to cool.
The shunt display on our setup regularly shows the Waeco CRX50 fridge drawing 4 amps and on the original Redline converter installation would give a maximum of two days off grid on the 110 Ah sla with no solar and the stupid split charger that they had installed on a Euro6 T6.
Managed to kill two cheapy 110Ah sla leisure batteries before finally ripping it all out and going solar, lifepo4 and B2B charger.
Managed to kill two cheapy 110Ah sla leisure batteries before finally ripping it all out and going solar, lifepo4 and B2B charger.
As Roadtripper says, the fridge is rated at 2.8a max power, so when with the compressor at full chat for an hour solid, it would only use 2.8Ah.
And in these temperatures, IE not 25 degrees heat, it won't take an hour to get down to temp. It's a 50l fridge with a tiny freezer compartment, not a massive house fridge.
If the battery is losing 10Ah per hour then it's not the fridge.
My CRX50 was using just under 3a when it was just powered on, it took about 40 minutes to get down to -14 in the freezer and 2 in the fridge compartment.
Thanks for the info everyone. In my apparently unscientific and incorrect testing so far, the fridge was on for 4 hours this morning powered by the leisure battery (so it had to get cold using more power and then stay cold). I switched it off and left it for another 90 minutes. Then checked again and the battery showed 86% 12.6V.
My next test will be to plug in and recharge the battery fully with the fridge on, so it gets cold while plugged in - this would be more realistic as usually we switch it on to get cold when driving to a campsite. Then I'll unplug it and leave the fridge on to see how quickly the battery discharges when the fridge is just maintaining a cold temperature rather than working hard to reach a cold temperature. Per the point made by @MK2Golf24v - I'll also add a few bottles into the fridge as advised by @AussieMick
Sorry for the naive testing and questions here, I appreciate everyone's insight. I may just be delaying the inevitable of course in terms of replacing the battery.
My next test will be to plug in and recharge the battery fully with the fridge on, so it gets cold while plugged in - this would be more realistic as usually we switch it on to get cold when driving to a campsite. Then I'll unplug it and leave the fridge on to see how quickly the battery discharges when the fridge is just maintaining a cold temperature rather than working hard to reach a cold temperature. Per the point made by @MK2Golf24v - I'll also add a few bottles into the fridge as advised by @AussieMick
Sorry for the naive testing and questions here, I appreciate everyone's insight. I may just be delaying the inevitable of course in terms of replacing the battery.
As above, your fridges maximum power is 2.8a - so let's say 3a. 4 hours at 3a per hour (3Ah) is 12Ah.
14% of a 110Ah battery is 15Ah.
Now, there is no way, even from ambient temperature, that your fridge will have had the compressor running for 4 hours solid. More likely it was running for an hour (max) to get it down to temp then around 1/3rd of the time. So 3a for an hour, then 1a per hour for the remaining 3 hours. Which puts us at 6Ah usage. It was probably less than 1a per hour actually! My CRX50 was using .75a (1% per hour of a 75Ah battery) recently when it was 10 degrees outside.
6Ah is less than half of the amount of charge your battery lost.
Just as another real world figure, our Sanjo CRX50 clone pulls 2.5 amps several times a day to keep wifeys Prosecco chilled to a palatable temperature, according to the LB App. You would never regret going the LifePo4 way! Getting cheaper all the time!
Totally agree with that. Always a silver lining. LiFePo4 can also be run right down without serious consequence if the same was to happen again and a 100ah gives you practically twice the run time of a 100ah AGM and will probably last 10 years. They pay for themselves in the long run.
So you’re recommending that if I need to replace the 100a AGM leisure battery, which seems likely, I should consider doing so with a LiFePo4 battery? Don’t mind paying a bit more if the benefits are as you say. Any drawbacks?
You can damage them if trying to charge below 5 C so make sure your solar is isolated in some way and same with any hook up for charging or if driving then the same thing by putting an isolator on the battery.
A replacement AGM battery isn't dirt cheap whereas lifepo4 batteries are getting cheaper with better specs by the day so get reading Lee @Dellmassive threads on the subject.
You'll see pictures of installs and input from the forum on these various threads which should take some of the fear out of installing your own power station.
A replacement AGM battery isn't dirt cheap whereas lifepo4 batteries are getting cheaper with better specs by the day so get reading Lee @Dellmassive threads on the subject.
You'll see pictures of installs and input from the forum on these various threads which should take some of the fear out of installing your own power station.
I’d get yourself one of these as mentioned earlier, asap if you haven’t already:
This will give you a log of what the battery is doing 24/7 so is a lot easier to monitor. Even if you replace the battery this is an essential in my book. I’ve had one on the LB from nearly day one and it’s really interesting to see what it gets up to while driving/parked/on EHU etc. and helps to understand “normal” behaviour. Takes a lot of the paranoia away
This will give you a log of what the battery is doing 24/7 so is a lot easier to monitor. Even if you replace the battery this is an essential in my book. I’ve had one on the LB from nearly day one and it’s really interesting to see what it gets up to while driving/parked/on EHU etc. and helps to understand “normal” behaviour. Takes a lot of the paranoia away
What @Stay Frosty said, the initial investment is a bit higher but avoid the bargain basement and look after it you should be good for 10 years with around twice the effective capacity in the same space.
Given the general drop in price I'd choose one with a low temperature cut off (or heater) built in and then you don't have to worry, generally this is also a sign of a decent battery design.
Don't ignore the low temp charge issue, it's for safety not just good practice, but it's worth the huge increase in benefits.
Given the general drop in price I'd choose one with a low temperature cut off (or heater) built in and then you don't have to worry, generally this is also a sign of a decent battery design.
Don't ignore the low temp charge issue, it's for safety not just good practice, but it's worth the huge increase in benefits.
One drawback is you will also need to fit a DC-DC charger to replace your split charger (assuming my memory from earlier in the thread is correct!) and you may need to replace some cabling depending on what you have already and what the new DC-DC needs.
Otherwise it’s an awesome upgrade and something I have just done in my van. I went with a Fogstar Drift 105ah battery (£369 but occasionally cheaper - I paid £299 during Black Friday sales) which has Bluetooth, low temp protection (vital as mentioned above), a heater and low voltage protection. I also had to swap my chargers as they were not compatible so fitted a Victron Orion DC-DC and upgraded the cabling from starter battery to DC-DC and Fogstar.
The result is great, giving me 4-5 days endurance for the fridge without solar or running the engine. It charges faster and is smaller and a lot lighter (10kg vs 30kg). I never feel the need for EHU now which makes site selection much more flexible (and cheaper).
So, cost is the main drawback as you may well need more than just the battery. If you want 2+ days off-grid then it’s definitely worth it imo. If you don’t need that then it is much cheaper to just replace the battery like-for-like and I’d suggest fitting a Victron Battery Protect (or similar) to prevent it getting over discharged in the future.
Yeah, completely agree that LiFePO4 is the way to go if you can, with a suitable DC-DC charger.
Not only will you gain the extra 20% charge from the DC-DC charging the LB to 100% instead of 80% with the split charge, you're gaining another usable 40% capacity thanks to the LiFePO4 battery.
So you'd be going from 30Ah usable with a 100Ah AGM at 80% SOC, to 90ah usable with a LiFePO4 at 100% SOC.
Not only will you gain the extra 20% charge from the DC-DC charging the LB to 100% instead of 80% with the split charge, you're gaining another usable 40% capacity thanks to the LiFePO4 battery.
So you'd be going from 30Ah usable with a 100Ah AGM at 80% SOC, to 90ah usable with a LiFePO4 at 100% SOC.
Just a note - I also have an Autohaus Ashton, and it's already got an Ablemail 30A DC-DC charger. Default is AGM profile (and I have the original AGM battery), but it is possible to re-program with a Lithium profile. Mine already has Lithium built in as an option. So should be no need for a new DC-DC. The catch is that the (only?) way to reprogram is by using the Ablemail bluetooth dongle, so you'll need one of those.
Best thing we ever did was get rid of AGM and install a 180ah lithium battery and 30A DC-DC charger. The VitriFrigo fridge / freezer works a treat as does everything else on the battery including ALL our 240volt (on inverter) stuff. Cannot remember last time we used EHU as park up use 240volts/12volts etc move next day or so (can park up for at least 3/4 days if there is enough sun (solar power) or drive to next stop and battery ready to go...........
awillyfootball
New Member
Hi there, I'm looking at lithium a battery at the moment, just out of interest what battery did you get? Thanks
