Charging lithium battery overnight with draw fridge running…
Brianvicki said
10:38 AM Feb 20, 2025
In the back of my 2014 Grand Cherokee, I have a 50amp slim lithium battery and has been working fantastic.
I also have a 30l draw fridge which works 24x7.
When driving I have a 25amp DCDC charger , works great and a solar panel on top when parked.
i have noticed though, when the car is in the garage overnight, that the 10amp battery charger (& previous charger) would charge all good, then when showing the battery is full charged, stop, as it should The fridge keeps going , but the charger doesnt kick in unless the charger is turned off and then on. In the morning the battery can be at 12.9 or 13.0
Doesn't sound like a very smart charger? Is is el-cheapo or very old?
B
Brianvicki said
11:16 AM Feb 26, 2025
I have two of them, they are Hardkorr 10 amp chargers, one in the van and the other in the car, both of them behave the same, will charge to full, then doesnt retry later and the battery charge drops as it is used. Only way to kick the charger back in is to power it off and then on.
I have sought feedback on them from Hardkorr, they were testing a unit over the weekend, just awaiting feedback , but yeah not fit for purpose.
Warren-Pat_01 said
09:27 AM Mar 3, 2025
Hi Brian,
Have you left the system go with the fridge running & nothing else charging the battery & see at what voltage the 10A charger kicks in? It will mean that you won't be able to be used for a while more than your normal overnight park.
I assume the chargers are set to 'Lithium'.
Brianvicki said
10:54 AM Mar 3, 2025
Yes I have done that, the charger doesnt kick in, it stays at full, even when the battery has dropped to 37%
Ive returned one unit and will return the other this week.
TimTim said
04:59 PM Mar 3, 2025
If I have the right manual your charger is an 8 stage charger but doesn't state whether it has a float mode. My reading is that it doesn't have a float mode in the normal stages of charging charging although it states it has a maintenance stage. Had to edit this post as I see the maintenance mode is only 2A. The other alternative is set it to power supply and it will give continuous power to both your fridge and battery.
The manual is very basic and does not give much information regarding the charging profiles and I did note this statement.
'The battery charger is designed for mobile use only and not for installation in caravans, mobile homes or similar vehicles.'
As has been posted it doesn't seem like it is a smart charger designed to be left on the battery although there are parts in the manual that give the impression you can and other parts that say disconnect after charging.
-- Edited by TimTim on Monday 3rd of March 2025 08:11:56 PM
Warren-Pat_01 said
10:32 PM Mar 3, 2025
Hi again Brian,
Like Tim I found the "handbook" rather ambiguous to fathom through.
Yes, it is microprocessor controlled but not to the degree that you want (or thought it would operate). The Maintenance setting only charges at a 2A "maintenance" charge to keep the battery going for as they say - keeping a small charge in a battery in eg an old car, boat, etc. It doesn't sense that the voltage has dropped & therefore has to recharge at the required float voltage of up to 10A.
The only way I can suggest you tackle the issue - other than getting a refund would be to connect it to a programable time clock to turn it on & off for set times during the day, night. The Victron that Tim suggests may cost a little more than what you paid - but often some companies offer special discounts. The same goes for Renogy.
I bought an el-cheapo MTTP solar controller from Kings early last year and as it was cheap, I kept a reasonable watch on it, found there was no Hi Voltage cut out & when I checked, it was putting 17.5v into my van's AGM battery! That was part of the problem - the other part was getting my money back!! As I paid for it via a credit card, according to Kings - I had to give them a bank account number for the refund & as my account had a substantial amount in it, I wasn't willing to give them that number! I leant my lesson - if buying anything from Kings, use cash!
TimTim said
08:15 AM Mar 4, 2025
Brian,
You will often find the cost of some Victron prioducts at about the same price as other brands and even if you are paying a little more then the technology and quality are worth it.
There are some good prices for chargers that provide higher current than the one you have.
In the back of my 2014 Grand Cherokee, I have a 50amp slim lithium battery and has been working fantastic.
I also have a 30l draw fridge which works 24x7.
When driving I have a 25amp DCDC charger , works great and a solar panel on top when parked.
i have noticed though, when the car is in the garage overnight, that the 10amp battery charger (& previous charger) would charge all good, then when showing the battery is full charged, stop, as it should
The fridge keeps going , but the charger doesnt kick in unless the charger is turned off and then on. In the morning the battery can be at 12.9 or 13.0
hope this makes sense.
any ideas?
Cheers
A fridge configured as a drawer.
B
I have two of them, they are Hardkorr 10 amp chargers, one in the van and the other in the car, both of them behave the same, will charge to full, then doesnt retry later and the battery charge drops as it is used. Only way to kick the charger back in is to power it off and then on.
I have sought feedback on them from Hardkorr, they were testing a unit over the weekend, just awaiting feedback , but yeah not fit for purpose.
Have you left the system go with the fridge running & nothing else charging the battery & see at what voltage the 10A charger kicks in? It will mean that you won't be able to be used for a while more than your normal overnight park.
I assume the chargers are set to 'Lithium'.
Ive returned one unit and will return the other this week.
If I have the right manual your charger is an 8 stage charger but doesn't state whether it has a float mode. My reading is that it doesn't have a float mode in the normal stages of charging charging although it states it has a maintenance stage. Had to edit this post as I see the maintenance mode is only 2A. The other alternative is set it to power supply and it will give continuous power to both your fridge and battery.
The manual is very basic and does not give much information regarding the charging profiles and I did note this statement.
'The battery charger is designed for mobile use only
and not for installation in caravans, mobile homes or
similar vehicles.'
As has been posted it doesn't seem like it is a smart charger designed to be left on the battery although there are parts in the manual that give the impression you can and other parts that say disconnect after charging.
https://hardkorr.com/cdn/shop/files/10A-Charger-Instruction-Sheet-V2.pdf?v=9454780438621185633
If you get a refund buy a Victron.
Hope that helps
Tim
-- Edited by TimTim on Monday 3rd of March 2025 08:11:56 PM
Like Tim I found the "handbook" rather ambiguous to fathom through.
Yes, it is microprocessor controlled but not to the degree that you want (or thought it would operate). The Maintenance setting only charges at a 2A "maintenance" charge to keep the battery going for as they say - keeping a small charge in a battery in eg an old car, boat, etc. It doesn't sense that the voltage has dropped & therefore has to recharge at the required float voltage of up to 10A.
The only way I can suggest you tackle the issue - other than getting a refund would be to connect it to a programable time clock to turn it on & off for set times during the day, night. The Victron that Tim suggests may cost a little more than what you paid - but often some companies offer special discounts. The same goes for Renogy.
I bought an el-cheapo MTTP solar controller from Kings early last year and as it was cheap, I kept a reasonable watch on it, found there was no Hi Voltage cut out & when I checked, it was putting 17.5v into my van's AGM battery! That was part of the problem - the other part was getting my money back!! As I paid for it via a credit card, according to Kings - I had to give them a bank account number for the refund & as my account had a substantial amount in it, I wasn't willing to give them that number! I leant my lesson - if buying anything from Kings, use cash!
Brian,
You will often find the cost of some Victron prioducts at about the same price as other brands and even if you are paying a little more then the technology and quality are worth it.
There are some good prices for chargers that provide higher current than the one you have.
https://www.springers.com.au/shop/category/power-conversion-battery-chargers-ac-chargers-134
My apologies as yoiu have to copy and paste the link.
Tim
https://www.springers.com.au/shop/category/power-conversion-battery-chargers-ac-chargers-134
-- Edited by TimTim on Tuesday 4th of March 2025 08:28:11 AM