Shoto 48V 100Ah 4.8kW batteries

[nightbyte]

My location: Western Cape, Inverter Axpert King and 9 Canadian 335 W panels and 2 x SDA10-48100 Lithium - iron batteries running in parallel.

I have two SDA10-48100 Lithium - iron batteries running in parallel coupled to a single Mecer Axpert King inverter.  I would like to ask the wise men of the Forum some questions about  these batteries.

The manual that came with the batteries recommends charge voltages as follows:  Minimum 53.2 V,   Typical 56.4 V  and  Maximum 57.5 V. 

I have set my inverter (programme step 26) to 53.2V.  The battery's BMS over voltage protection is initiated at 54.0 volts.   I am concerned that 53.2 V  might be too low, i.e inefficient.  Axperts tend to over shoot the charge voltage somewhat and I was hoping to increase this slightly to between 53.3 V and 53.5 V, thus still allowing some over head.   Could Forum members please comment?

There is no reference to a Float voltage setting in the Shoto documentation that I have.  I have therefore set the inverter (programme step 27) to 53.0 V, i.e. 0.2 V below the charge setting of 53.2, I would do the same for any higher charge setting used for the charging value.  Could Forum members please comment?

I have not used the Equalization programme in the inverter's programme, steps 33 through to 39 as I believe that this is intended for Lead Acid and Gel type batteries and consequently not appropriate to a lithium - iron set up.   If I did use it (unlikely), I would set it to the Float voltage setting value.  Could Forum members please comment?

The 6-bit dial switch on the batteries is not well documented in the manual and I am unsure of the correct settings for the relevant switches. Currently I have switch 1 on the first battery set to 1 ON all others OFF, which I believe identifies it as the master battery. Battery 2 switch is set to 2 ON and all others OFF which I believe identifies it as the slave battery. Could Forum members please comment?

Finally, the RS485 Comms cables linking batteries to the inverter in what the manual refers to as a cascade system.  Where can I source such cables from in the Western Cape (battery to battery and battery to inverter) and are they really necessary?  I have read mails on the form that suggest that Axpert inverters don't talk to the battery's BMS, but not sure if this applies to the King inverter. These mails further suggest that it is only necessary to link the batteries together in a master/slave configuration.  Any information that  Forum members could provide on this issue would be most helpful. 

 

[Anish]

I’ve have a similar setup. 2x Shotos sda100 m14’s in parallel with 2 parallel Growatt 5kvas in the setup. No comms cable available /designed anywhere from what I gather. 
 

I have float set at 54.3 and bulk at 54.0v(even though they are lifepo4) . Back to grid at 48.0v and back to battery at 52.0v. Cut off voltage is 46v. I get about 6kw out of the stack. Dropping the ‘back to grid’ to 47v or below has resulted in a few bms alarms previously. 
 

pity there’s no comms cable for these as they are pretty decent batteries used widely in the communication industry 

[jykenmynie]

The first thing you must check is whether you have the 15 cell or 16 cell Shoto. They make both (and do not seem to indicate this anywhere on the battery) and the charging parameters between the two would be very different. The only way I know of that it could be checked would be plugging a laptop in and reading the BMS output.

I had one of these batteries and saw some of the readings in the BMS but subsequently returned it. I did not want a battery/inverter that are unable to communicate. That said, the spec sheet of the battery looked good, but only time would tell if the discharge ability is sustainable in the long run.

[nightbyte]

Thank you for the comment.

It is a 15 cell Shoto.

Where did you get the software to read the BMS? 

If you do not mind me asking, could you name the supplier that you returned the battery to?

With the help of friends I have made up a comms cable and a comms cascade cable which seem to be working.  At least no negative consequence from fitting them and the inverter (Axpert King) seems happy with the arrangement.  However, there is no indication on the LCD that reports this.  Wish that I could find out more technical information on this battery, being able to read the BMS would help. 

Did you perhaps keep a copy of the readings from your BMS?

I note that many of the larger Solar equipment suppliers are selling this battery.  It would help us all, if other Users of the Shoto could comment on their experiences with them. 

I still have to positively identify who the main supplier into the RSA is.  Shoto China's RSA Representative has mailed me with the name of a company called TAGSA which I cannot locate on Google, so not sure if this will lead anywhere. I was hoping that they would have a support section.

[jykenmynie]

20 hours ago, nightbyte said:

Where did you get the software to read the BMS?

I did not have it myself. The technician of the supplier I bought from came around when I wasn’t happy with the communication issues between the inverter and batteries they sold me.

After I’ve returned mine to the supplier that sold it to me in the first place (technically I guess they sold to my electrician) I had it all replaced with a Victron and Pylontech system. I unfortunately did not keep anything relating to it.

I’ve spoken to other installers afterwards who mentioned they found out from the main distributer of Shoto batteries that currently there is no way any inverter would be able to communicate with these batteries. They are working on a solution, but wasn’t clear when it will be ready.

I’ll pm the details of the supplier.

[nightbyte]

Thank you for the information.

[WillieD]

On 2020/08/24 at 7:35 AM, nightbyte said:

Thank you for the information.

I also have Shoto batteries and the same questions as you. It was interesting following your thread but what has happened since August because I am still in the same dillema Could you share some info please

[Chloe]

5 minutes ago, WillieD said:

I also have Shoto batteries and the same questions as you. It was interesting following your thread but what has happened since August because I am still in the same dillema Could you share some info please

Could I make a suggestion: In the Commercial section on this forum you'll find Backbone energy they'll be able to assist with your questions.

[MarkK]

How do you connect your laptop to the shoto? I have various cables that can with but the manual doesn’t explain. 
I have loaded the cd that came with into my laptop. It’s called Watch Power. 

[nightbyte]

Shoto battery installation update

After some 6 months of testing and adjustment, the following is a summary of my current settings. Please note that these are the settings that best suit my system  (5kw Axpert King with 2 Shoto lithium iron 4.8kw batteries). Yours may be quite different.

Axpert King Program settings

01 Output source priority - SUB

My normal system load is 8 to 10% i.e. about 450W but can go to 1650w i.e. 40 to 50%. System can carry 4 hours of load shedding at 8 to 10% load from batteries and remain above 80% DOD.

02 maximum charging current - 40 Amp

10 Amps from utility and 30 Amps from solar. (Program Watch-Power used).

05 Battery program - Set To Use

011 Utility charging - Set to 10 amps

012 Back To Grid - 48v (per Coulomb's recommendations)

013 Back To Discharge - 50v (per Coulomb's recommendations)

016 Solar Energy Priority - SbL Udc

026 Bulk Charging - 52.5v This is 3.5v per cell for a 15s battery

027 Float charging 51.8v this is 3,45 per cell

These settings do not give a BMS alarm condition. The BMS alarm parameters are: Alarm 3.7v per cell, alarm recovery 3.34v per cell,  protection 3.65 v per cell.  My values for 026 and 027 are conservative, but provide some overhead to prevent drift into the BMS alarm states (Discussed with Coulomb). When set to Shoto recommended higher values of 53.2v, I experienced occasional alarm conditions.  This could have been due to solar conditions. I have 9 x 355W panels with output average 125 to 128v

029 Low DC Cut-Off - 46.7v (gives DOD maximum of 80%)

The difference between 027 and 029 is 1.3v  (Slightly less than the 1.5v recommended by Coulomb).

Other matters:

The Shoto manual that came with my batteries is identified as version V 1.0  The importers were not able to assist me with an updated version.  

Comms cables, these are RS485 / RJ45 - 8 pin. I made up a set as per the diagrams in the manual.

Batteries are configured to master (switch 01 on battery selected as master) and slave (switch 02 on battery selected as slave). Cascade cable as per manual.

There is currently no BMS / Inverter / communication interface system for the Shoto SDA10-48100 available in the RSA that I am aware of (such as exists for Pylontech batteries). if you have knowledge of such, please advise.

My Watch-Power program did not work from the supplied CD.  Mecer Cape Town's technical support very kindly provided me with a download that did.

I would be interested to read of your experiences with these batteries and sources of support for them in the RSA.

Thanks in anticipation. (December 2020) 

[hannesk]

Thanks for the update nightbyte, I have the exact 2 x Shoto SDA10-48100L5 in parallel.

I used your bulk and float settings on my Victron ESS and MPPT as I had daily High DC Ripple warnings that I suspect using 53.3V Bulk and Float. I will monitor the error logs and report back.

 

I'm only concerned that 52,5V Bulk and 51,8V Float will not charge the 2 X Batteries to 98% SOC at least, what is your research in this regard?

 

[nightbyte]

Thankyou for your response hannesk.

The settings provide a 100% state of charge as reported by the Watch-Power programme on my Axpert King and are based on Coulomb's advice and guidance.   I have no other way of checking the charge percentage.  I was advised that Axpert inverters can have a tendency to overcharge, hence the conservative settings. You can try 53.2v for bulk (Shoto's recommended minimum for bulk) and 53.0V for float.  However, you may experience some overcharging, if you have robust solar conditions.  The BMS alarms at 54V on my system. 

If you do decide to increase the settings slightly, please monitor the results and provided feed back.  

[hannesk]

Changed, lets give it a week and check the logs. Thanks for the recommendation

 

[MarkK]

On an off grid situation what should the minimum voltage be. I heard if it goes too low it goes into limp mode and needs to be reset by factory. 

[nightbyte]

Thankyou for contributing to this group.

This is a rather unusual question and one that I have only limited knowledge and experience with.  I have experienced a defective BMS programming issue which caused the battery to go to a very low voltage and then shutdown completely.  It then refused to accept a charge and had to be returned under warranty to the supplier. They reportedly re-programmed the BMS and reset the battery.  Since then it has operated as specified in the manual.

The manual that came with my battery stated that the BMS is  provided with the following low voltage protections:

Alarm recovery value 43.2v,

Alarm value 42v, and

Protection value 40v. 

My understanding is that the BMS shuts down the battery at 40v and places it in a standby mode. To re-activate the battery it must be placed on charge by the inverter and the voltage raised above 43.2v The battery can remain in the standby mode for sometime (the manual suggests 6 months and then needs to be re-charged).

My inverter's low cut off voltage is: Setting 029 Low DC Cut-Off - 46.7v (gives DOD maximum of 80% on a 48V battery bank). This is well above the BMS values, but that is because I do not want the batteries to drop below 80% depth of discharge and potentially damage the batteries. With my average load of around 450W the normal 2.5 hour load shedding period sees a DOD of 68 to 70%.

I am conservative by nature and would suggest a settings below 46V (around 90% DOD on a 48v battery bank) should be avoided as battery life could be negatively impacted.

Hope this assists you.  Please provide feedback on your experience.

[VanFam]

Hi All,

I have been using my 3kw, 48v Axpert inverter with 4 x Lead acid batteries for just over 4 years. I upgraded to 6 x 390watt JA Solar Mono panels (3 x 2 strings) last year. Then yesterday I decided to upgrade to 1 x Shoto SDA10-48100L5, Lithium batteries is new territory for me and need advice / guidance.

@ nightbyte - I used your suggested settings posted December 30, 2020 with a few exceptions (Settings 01, 02 and 016). Even though you have a 5kw inverter with 2 x Shoto batteries I suspect the settings will work for my setup. I also prefer 80%DOD to prolong battery life.

1)      Before reaching the 52.5v Bulk charging (setting 026) the 4 x SOC LED lights are off, meaning as per battery its fully charged, correct.? But on inverter display it’s still charging the last bar (charging 75% to 100%). Last night at 23H00 I switched off my Eskom while still on 52.4v, afraid of damaging the battery, charging since 16H45. Still not showing fully charged on my inverter though, only displaying 3 out of the 4 bars.

2)      Then after roughly using 193watts for 4hours the inverter displayed 49.4v and that 2 bars are gone meaning as per inverter the battery is on 50%. But on battery all 4 x SOC LED lights are still green.

This does not make sense to me, what am I doing wrong?

My settings

01 Output source priority - UTI

To manually switch Eskom On or Off

02 maximum charging current - 20 Amp

Charging current {current-limiting} - 20Amp as per Spec sheet

Charging current {Maximum}  - 100Amp as per Spec sheet

Again afraid of damaging the battery when I set to 40 Amp, new territory...

05 Battery program - Set To Use

011 Utility charging - Set to 10 amps

012 Back To Grid - 48v 

013 Back To Discharge - 50v

016 Solar Energy Priority - CSO (Solar First)

Inverter only has CSO - Solar First and CUT - Utility First

026 Bulk Charging - 52.5v This is 3.5v per cell for a 15s battery

027 Float charging 51.8v this is 3,45 per cell

Any guidance / advice would be greatly appreciated.

Thank you in advance...

Edited February 14, 2021 by VanFam

[VanFam]

1 hour ago, VanFam said:

02 maximum charging current - 20 Amp

Charging current {current-limiting} - 20Amp as per Spec sheet

Charging current {Maximum}  - 100Amp as per Spec sheet

Again afraid of damaging the battery when I set to 40 Amp, new territory...

As per Battery Spec sheet... Apologies. 

[nightbyte]

Good day to you Vanfam. Thankyou for contributing to this Shoto thread. Firstly 52.5v is a conservatives setting well within Shoto's recommended charging values and  is extremely unlikely to harm your LI battery.

The battery LED lights are an accurate gauge of what is happening, as they are directly part of the BMS inside the battery. My experience is that the inverter's indictor bar graph display is not nearly as accurate and just give a general indication.  For example when your battery is fully charged and in float mode battery LEDs will be off, except for 1 (far right) which should just flash, about once a minute indicating that the battery is in float charging.

Here what I suggest you try. Use a hand held multimeter set to about 75v or more on the DC range and measure the battery voltage directly at the battery terminals, red to positive, black to negative. Do this for the different battery led light displays and record the voltage at 4,3, and 2 LEDS also when only 1 LED is flashing in float mode. These are the real voltages in your battery (SOC).  Now compare these to the inverter bar graph display.

The inverter charge state bar display has been reported by other users and has a reputation for inaccuracy when in user mode for Lithium iron batteries. I believe that Axpert inverter software was originally configured for non lithium batteries, and while the inverter works perfectly with Lithium batteries in the user mode this  inaccuracy of the indicator battery indicator bar may be a hang over from the sealed battery period. 

I too was originally confused by this conflict of display conditions.  I performed the multimeter testing at different conditions as suggested above until I was satisfied with what was the real voltages in the battery compared to the bar graph on inverter. Incidently the inverters load measurement bar graph appears to be accurate and believable.

Charging current: I have 2 batteries and used 40Amp and have not experienced any alarms. Yes, 20 amp is probably fine. The Shoto battery manual says charging current setting +/- 1C3, which I take to mean 33.3 Ah. The Axpert inverter programme (setting 02) states: max charging current = Utility charging (programme 011) current + solar charging current. If you set 011 to 10ah, then 10Ah  + 30Ah = 40Ah (as in setting 02). In your case 10Ah + 20 = 30Ah.

Tired of having to multimeter the battery terminals I have installed an inexpensive digital voltmeter (fused) adjacent to the battery bank which allows me read directly the battery voltages at the flick of a switch. The inexpensive digital voltmeter was obtained from Communica, Cape Town and works well.

Further, I strongly suggest that you install the Axpert PC monitoring software that you should have received with your inverter. if you experience issues with this software as I did approach Mecer Cape Town Technical Support. They were excellent and provided me with working updated software (ask for Craig).

Please provide  feed back on your experiences.

Regards.

[VanFam]

Good day Nightbyte. Thank you for the feedback and advice, its highly appreciated. I will do the tests as you advised and will provide feedback as soon as I have enough info. I will also get in touch with Mecer Technical Support regarding the software.

Once again Thank You.

Regards. 

[alkafak]

Hello Folk

i agreed all of you, i have setup in my infini solar 3Kw plus to 48V for cut off as i know this is 80% DoD for 15S Lithium batteries

but, my inverter still showing 66% remaining capacity of batteries, i don't know this situation true or false, because batteries show 3 Led steady on and 1 is blinking, refer to manual this condition indicate the remaining is 75%-99% capacity

let me know for any suggestion

 

Alkafak

[Anish]

9 hours ago, alkafak said:

Hello Folk

i agreed all of you, i have setup in my infini solar 3Kw plus to 48V for cut off as i know this is 80% DoD for 15S Lithium batteries

but, my inverter still showing 66% remaining capacity of batteries, i don't know this situation true or false, because batteries show 3 Led steady on and 1 is blinking, refer to manual this condition indicate the remaining is 75%-99% capacity

let me know for any suggestion

 

Alkafak

The battery status  indicated on your battery is correct. The inverter is reading SOC based in voltage and is a ‘guess-timate’ according to voltage dissociation curve and is influenced by rate of discharge . I wouldn’t believe the SOC on the inverter

Shoto still haven’t created a reliable communication interface for axpert/Growatt type inverters  it’s a pity because they are quite solid batteries and right now we are purely using them as ‘lead acid battery replacements’ in USE mode 

 

 

 

 

 

[nightbyte]

I have reduced my setting 02 to provide a  maximum charging current of 20 Amps.

The Axpert inverter programme (setting 02) states: max charging current = Utility charging (programme 11) current + solar charging current.  So set 11 to 10Ah, then 10Ah  + ? Ah = 20Ah (set in 02).  Thus 10Ah + 10Ah  = 20Ah maximum charging current.  Did this to reduce charging load and inrush current on inverter capacitators. Should also prolong battery life (I hope). Have not experienced any negative results and system still recharges in about 3 to 4 hours after load shedding with batteries at 70% DOD and a draw off load of about 400watts.

Comments please ?

 

[Ratoka]

I have used DEYE inverter with SHOTO SDA10-48100. The inverter communicated without problem with the battery BMS using RJ45 cable connected to the RS485 ports.

Edited February 20, 2021 by Ratoka

[Salie]

Hi Ratoka. Have a similar setup to yours. My installer just completed. 1)He plugged the battery comms cable on CAN and battery setting on "Use Batt %" and not lithium(Alarm goes off when trying to change to lithium-tried changing to Rs485A with no luck). Is this correct? 2) My usage shown on the touch screen only shows usage on the backup load and not overall house usage. What is potentially wrong here as I see when the oven, stove or geyser is switched on nothing happens with the usage. Same issue in app. Any assistance would be appreciated. 

[Francois Raath]

I intend replacing my Microcare 5kW inverter with an Axpert 5kW inverter with Litium-ion batteries.

Does anyone know if there is a setting and or ability of the Axpert inverter so as to limit the amps drawn from the battery so as to protect it against too rapid discharge and shortening its lifespan? The recommended standard discharge rate is 0.2C and rapid discharge rate is 0.5C (0.2C for 4.8kW/48V battery is 20 Amps and 0.5C is 50 Amps)

Any advice on this will be appreciated.