Hi,

I have a Sunsynk 8kw and 60kw lifepo4 battery pack. All works well, but I only have a 4 hour charging period on my Octopus tariff and in winter I'm not able to fully charge my batteries. Could someone recommend a way of being able to fully charge? Not sure if this is the right section to ask. 

Thanks 

Peter

Edited January 15, 20242 yr by pedro54
Added extra comment

Hi @pedro54 

Do you have panels if so how many and what wattage, and are you able to add more? You will need to max out the number of panels you can mount, or get higher rated (+550w panels). 

Very high-level 2c. The Sunsynk inverter has a maximum charge rate of 190A, so call that 760Ah you can replenish within a 4-hour period.

If you're charging at the battery's max charging Voltage (eg. 57.6V on a Sunsynk lithium battery), you'd be replenishing no more than 43.6kWh in a 4-hour period into your 60kWh battery bank based on the inverter's limitations.

If you need more, you'd have to think of alternatively adding a second inverter in parallel, or replacing it with the 16kW Sunsynk that can deliver 275A charge rate. This is on the understanding that your home's supply can handle more than just 63A at 230V; you should rather be looking upwards at an 80A supply at least, or more. Otherwise your options are charging outside the preferred tariff rate, or adding solar panels to charge during the day.

This is assuming the batteries can take that charge, ie. if it's a 0.5C charge rate like on the typical Sunsynk battery or Pylontech or similar, you should be just about okay, but anything lower like 0.2C charge rate would require a battery upgrade.

4 hours ago, Greglsh said:

Hi @pedro54 

Do you have panels if so how many and what wattage, and are you able to add more? You will need to max out the number of panels you can mount, or get higher rated (+550w panels). 

Hi, thanks this is in winter when I don't get enough solar. In summer it's fine.

3 hours ago, GreenFields said:

Very high-level 2c. The Sunsynk inverter has a maximum charge rate of 190A, so call that 760Ah you can replenish within a 4-hour period.

If you're charging at the battery's max charging Voltage (eg. 57.6V on a Sunsynk lithium battery), you'd be replenishing no more than 43.6kWh in a 4-hour period into your 60kWh battery bank based on the inverter's limitations.

If you need more, you'd have to think of alternatively adding a second inverter in parallel, or replacing it with the 16kW Sunsynk that can deliver 275A charge rate. This is on the understanding that your home's supply can handle more than just 63A at 230V; you should rather be looking upwards at an 80A supply at least, or more. Otherwise your options are charging outside the preferred tariff rate, or adding solar panels to charge during the day.

This is assuming the batteries can take that charge, ie. if it's a 0.5C charge rate like on the typical Sunsynk battery or Pylontech or similar, you should be just about okay, but anything lower like 0.2C charge rate would require a battery upgrade.

Hi, I don't even seem to be getting those values. The Sunsynk app has charging at 143A during that period. I have 4 battery packs using Seplos 200A BMS.

On 2024/01/15 at 1:34 PM, GreenFields said:

Very high-level 2c. The Sunsynk inverter has a maximum charge rate of 190A, so call that 760Ah you can replenish within a 4-hour period.

If you're charging at the battery's max charging Voltage (eg. 57.6V on a Sunsynk lithium battery), you'd be replenishing no more than 43.6kWh in a 4-hour period into your 60kWh battery bank based on the inverter's limitations.

If you need more, you'd have to think of alternatively adding a second inverter in parallel, or replacing it with the 16kW Sunsynk that can deliver 275A charge rate. This is on the understanding that your home's supply can handle more than just 63A at 230V; you should rather be looking upwards at an 80A supply at least, or more. Otherwise your options are charging outside the preferred tariff rate, or adding solar panels to charge during the day.

This is assuming the batteries can take that charge, ie. if it's a 0.5C charge rate like on the typical Sunsynk battery or Pylontech or similar, you should be just about okay, but anything lower like 0.2C charge rate would require a battery upgrade.

Why 2c? My cells are 304ah EVE. What settings would I need to change to get 190A or near it?

1 hour ago, pedro54 said:

Why 2c? My cells are 304ah EVE. What settings would I need to change to get 190A or near it?

That's got nothing to do with any solar specifications or equipment.

My 2c is just "my two cents' worth," in other words, my humble opinion, at a high/vague level of thinking, without specific details behind it. Sorry, maybe I should change my phrasing if it's causing confusion.

Edited February 22, 20242 yr by GreenFields

On 2024/01/15 at 7:13 PM, pedro54 said:

I have 4 battery packs using Seplos 200A BMS

each pack its own 200A Seplos BMS? if only one BMS, then your charging limit would be that 200A BMS...

2 hours ago, pedro54 said:

Why 2c? My cells are 304ah EVE. What settings would I need to change to get 190A or near it?

Check under the inverter's settings, look for the battery settings, and see if you've got any limits set there on the charge rate from grid, or a global charge limit.

Otherwise look for the Li-BMS page, and see if the BMS is defining any specific charging limit. I don't see anything in the amount of battery capacity you have, or in the 0.5C-rating of the cells, that suggests that you shouldn't be able to reach 190A.

I don't have a Sunsynk, but the Deye-brand, so my menu structure is a bit different.

If you have 304Ah cells then you most likely have 4 packs in parallel? 

You need to make sure the charge rate on each bms is set the same. Make sure your inverter max charge amps is set to 190A.