Renogy 12V 200Ah drop-in LiFePO4 battery

[MtB]

I bought one of these a short while ago and installed it in parallel with my 2 x 100Ah LA domestic battery bank, as a hybrid installation. 

 

It was £879.99 direct from the Renogy site and so far I'm actually really pleased with it. (I really hope I'm not gonna regret writing that as time progresses.)

 

A few initial observations. Firstly the built-in BMS is proprietary and a bit weird. Horribly dumbed down probably to suppress the stupid complaints/technical questions from muppets that better info would generate. I'll post up some screenshots tomorrow. The main problem I have with it is the cell voltages are only reported to one decimal place but given the mass market they are selling this into, this seems sensible! Secondly there is no info on how the reported SoC is calculated. My guess is from AH counting, but it could be just from more accurate cell voltage monitoring despite the one decimal place reporting in the app. Thirdly the documentation is similar, hopelessly sketchy. But then it was a really cheap purchase! 

 

One odd thing is the weight of the thing. It weighs approx 27kg (for 200Ah) but at the same time I bought a LifeBatteries 100Ah drop-in too for another boat (£490, and for comparison) which weighs far less than half at 10.5kg. Odd.

 

I've yet to install the LifeBatteries one but will post my impressions in due course...

 

 

Edited December 28, 2022 by MtB
Thread title change

[Naughty Cal]

From memory our Sterling Amps 100ah drop in is about 13kg.

 

The SOC on ours is calculated by AH counting which is next to useless when the BMS doesn't register loads under 2 amp, which is most of ours. BMS still claims to have done 0 cycles despite it being fitted for over 12 months now.

 

We just ignore that and look at the cell voltages instead. Which in our case do report to three decimal places which is rather more useful.

 

Edited December 28, 2022 by Naughty Cal

[cheesegas]

A lot of drop in batteries use a version of the now ubiquitous Chinese made JBD battery management board. This means that you can use any app on any battery. Sterling also use a JBD board, so you should be able to use the xiaoxang-bms app to control it, which gives you access to all the parameters (for about £1.99 I think). 

 

However, you need an external shunt based battery meter as the SOC seems to be calculated from cell voltage and amp hour counting. It isn't very smart though - if it's almost empty, resting at 12.8v and you apply a high charge current of 70-80a, the BMS will report it as full despite being far from it. The xiaoxang app allows you to customise the cell voltage relationship to SOC, but I don't suggest playing with it unless you take a full backup first.

Anyway...the early Renogy batteries also used a JBD BMS variant, so you may be able to connect to it with the xiaoxang app. I don't know what BMS the later ones have though, it may be entirely proprietary, or modified enough that only their app works. 

[rusty69]

8 hours ago, MtB said:

One odd thing is the weight of the thing. It weighs approx 27kg (for 200Ah) but at the same time I bought a LifeBatteries 100Ah drop-in too for another boat (£490, and for comparison) which weighs far less than half at 10.5kg. Odd.

That is odd. I did initially wonder if the weight difference was because Renogy use pouch cells, but as these are typically lighter, it seems unlikely. I know that lifebatteries says they use Eve (prismatic) cells, and the weight of theirs differ from the fogstar ones of same badged capacity.

I wonder if the difference lies in the actual useable capacity of the cells in the box.

 

Have you managed a capacity test as yet?

[MtB]

 

 

Here's a screenshot of the app. 

 

The whole of the app is bigger than the screen so I have to scroll down to get the battery voltages. Second screenshot of this to follow.

 

 

 

 

[MtB]

 

 

And there you have it, the full extent of the info provided by the Renogy app.

 

 

[cheesegas]

Have you tried the xiaoxang app as I mentioned?

[booke23]

6 minutes ago, MtB said:

 

 

Here's a screenshot of the app. 

 

The whole of the app is bigger than the screen so I have to scroll down to get the battery voltages. Second screenshot of this to follow.

 

 

 

 

 

I like that it has a heating module, very useful. Is that totally automatic or can you configure the temp it kicks in at?

I am however a little concerned that your phone battery is only 56% at 08:36!

Edited December 28, 2022 by booke23

[MtB]

19 minutes ago, booke23 said:

 

I like that it has a heating module, very useful. Is that totally automatic or can you configure the temp it kicks in at?

I am however a little concerned that your phone battery is only 56% at 08:36!

 

 

Nope, no heating module. That "Off" can't be changed! 

 

Other Renogy batteries have heaters but not the 200AH.

 

My LifeBattery one has heaters though, and they operate automatically according to the bod there in chat. If the battery temp is below <some value, prolly 0C > and you try to charge it, the charge current is sent to the heaters not the cells, until the cells are up to the target temperature, then it automatically switches to charging the cells. Quite neat, if it works. 

 

 

[MtB]

And no need to worry about my phone battery. You'll notice it has gone up to 44% at 10.21am! 

 

 

[Alan de Enfield]

 

43 minutes ago, MtB said:

And no need to worry about my phone battery. You'll notice it has gone up to 44% at 10.21am! 

 

 

 

 

Is 44% SoC really an increase on 56% SoC ?

[MtB]

11 minutes ago, Alan de Enfield said:

 

 

 

Is 44% SoC really an increase on 56% SoC ?

 

 

I always catch at least one. and today its YOU! 

[TheBiscuits]

1 hour ago, cheesegas said:

Sterling also use a JBD board, so you should be able to use the xiaoxang-bms app to control it, which gives you access to all the parameters

 

Sterling have password locked their BMS to stop customers playing with settings.

 

Cracking the password voids the 5 year warranty so I haven't (yet!) - and I've already swapped one battery because the Bluetooth module failed.

[Naughty Cal]

2 hours ago, cheesegas said:

A lot of drop in batteries use a version of the now ubiquitous Chinese made JBD battery management board. This means that you can use any app on any battery. Sterling also use a JBD board, so you should be able to use the xiaoxang-bms app to control it, which gives you access to all the parameters (for about £1.99 I think). 

 

However, you need an external shunt based battery meter as the SOC seems to be calculated from cell voltage and amp hour counting. It isn't very smart though - if it's almost empty, resting at 12.8v and you apply a high charge current of 70-80a, the BMS will report it as full despite being far from it. The xiaoxang app allows you to customise the cell voltage relationship to SOC, but I don't suggest playing with it unless you take a full backup first.

Anyway...the early Renogy batteries also used a JBD BMS variant, so you may be able to connect to it with the xiaoxang app. I don't know what BMS the later ones have though, it may be entirely proprietary, or modified enough that only their app works. 

The board on our Sterling battery is a Daly.

46 minutes ago, TheBiscuits said:

 

Sterling have password locked their BMS to stop customers playing with settings.

 

Cracking the password voids the 5 year warranty so I haven't (yet!) - and I've already swapped one battery because the Bluetooth module failed.

The password is 123456

[Jen-in-Wellies]

30 minutes ago, Naughty Cal said:

The password is 123456

The same as my bank account. Nice and easy to remember. 😀

[ditchcrawler]

5 hours ago, cheesegas said:

A lot of drop in batteries use a version of the now ubiquitous Chinese made JBD battery management board. This means that you can use any app on any battery. Sterling also use a JBD board, so you should be able to use the xiaoxang-bms app to control it, which gives you access to all the parameters (for about £1.99 I think).  

Mine was a free download I also have the Overkill Solar App running on Android

[MtB]

First Renogy app fault revealed. The app can't do basic arithmetic.

 

Cell voltage reporting is unhelpfully limited to one decimal place. But the cell voltages reported do not always add up to the whole battery voltage reported by the app.

 

Here we have the four cells each being reported at 3.1V adding up to 12.4V, yet the battery voltage is being reported as 12.7.

 

Looks to me as though the cell voltages are therefore being simply truncated, rather than rounded up/down to the nearest 0.1V. Even if all four cells were actually 3.150V each this would still only add up to 12.6V, but here, the app claims 12.7V.

 

 

 

 

 

Edited December 28, 2022 by MtB
Redundant words removed

[Naughty Cal]

Doesn't seem overly accurate. 😕 

[BEngo]

If the app is truncating the cell and total  voltages  after addition then actual cell voltages over 3.175 V will give a reported battery voltage of 12.7.

 

Still, given the sensitivity of voltage at the top knee, ad the small variation of SOC with voltage it is not very helpful.

N

 

[nicknorman]

Firmware version V0100. Otherwise known as V1. Is there a firmware update available?

[PeterF]

The individual cell voltages and total cell voltage may be being measured by different sensors which have their own inaccuracies and may therefore read slightly different. The total voltage is not necessarily the mathematical sum of the 4 cell voltages.

[MtB]

14 minutes ago, PeterF said:

The individual cell voltages and total cell voltage may be being measured by different sensors which have their own inaccuracies and may therefore read slightly different. The total voltage is not necessarily the mathematical sum of the 4 cell voltages.

 

 

An intriguing assertion.

 

How can the total battery voltage ever be anything other than the sum of the individual cell voltages? 

 

 

[cheesegas]

On 28/12/2022 at 10:25, cheesegas said:

Have you tried the xiaoxang app as I mentioned?

 

On 28/12/2022 at 10:02, cheesegas said:

.Anyway...the early Renogy batteries also used a JBD BMS variant, so you may be able to connect to it with the xiaoxang app. I don't know what BMS the later ones have though, it may be entirely proprietary, or modified enough that only their app works. 

 

3rd time lucky, then I'll give up - have you tried using the xiaoxang-bms app? There's a good chance the Renogy BMS is based off the JBD board.

[MtB]

23 minutes ago, cheesegas said:

 

 

3rd time lucky, then I'll give up - have you tried using the xiaoxang-bms app? There's a good chance the Renogy BMS is based off the JBD board.

 

Yes sorry I should have answered. Thank you for this suggestion!

 

I have it installed on my phone for the other Li battery. But it fails to detect or connect to the Renogy battery.

 

EDIT:

 

Actually, revise that. What I actually have is the Overkill JBD app, which I thought was the same thing but maybe it isn't. I'll try downloading the xiaoxang-bms, vanilla flavour.

 

 

 

Edited December 29, 2022 by MtB

[nicknorman]

19 minutes ago, MtB said:

 

 

An intriguing assertion.

 

How can the total battery voltage ever be anything other than the sum of the individual cell voltages? 

 

 

it’s a valid point. With my own BMS I have a fancy chip that measures the individual cell voltages to 3 decimal places. The tech to do that is quite complicated but fortunately someone else developed that! There is also of course an analogue-digital converter built into the microprocessor, so it is a trivial matter to measure the overall voltage. Bearing in mind eg a bad connection in one of the sense wires might throw off a cell voltage reading I thought it prudent to display 2 numbers, one being the sum of the 4 cell voltages, the other being the total voltage as measured by the AtoD. Of course they SHOULD be the same, but I regarded it as a bit of an error-check. When you are making critical decisions (disconnect battery) based one data from one wire (a cell sense wire) it makes sense to include some vague sort of error monitoring, the only thing I haven’t done is to include any code to “do something” if the values disagree. But so far, they haven’t!