Possibly a dumb question to a dumb lithium battery…

Just smiffy

Just smiffy

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Question…

If I got a Bluetooth lithium battery and got the equivalent lithium battery but without the Bluetooth and connected them as one big battery would the Bluetooth in one give readings and results for both batteries, or would it give an indication of state of charge on the dumb battery as a whole.?

I’m sure I know what I mean but can you make sense of that …😆🤷🏼‍♂️
 
My lithiums all have different serial numbers so come up as a list on the app. Apart from the voltage I can’t see how any other info from the non-Bluetooth would be displayed.
 
I have two without bluetooth and one with BT.
All connected together and works fine.
There will be no info on the others as there is no comms.
 
The next question to Garrys thoughts may be ....

If you have a Bluetooth lithium and a non Bluetooth one and they were the same size. Would the Bluetooth one give the same values on the app and would that equate to the non Bluetooth one? Ie would they charge equally ?
 
You would have to assume that the soc and discharges etc were the same for each battery showing on the one battery app. It's best to wire them such that your taking a ×ve off one and a -ve off the other.

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Simple answer No.

Also always best to fit a shunt with Lithium as the Bluetooth BMS can't read currents below 1 amp and you find when not using the van so only low current being drawn the BMS won't register so it reports state of charge far higher than it actually is.
 
suavecarve said:
The next question to Garrys thoughts may be ....

If you have a Bluetooth lithium and a non Bluetooth one and they were the same size. Would the Bluetooth one give the same values on the app and would that equate to the non Bluetooth one? Ie would they charge equally ?
Click to expand...
If they been together as a bank for few cycles yes. I found mine after 4-5 cycles to contribute very close to equal to their capacity. Reading the amps on the shunt as total, and the amps on the BT bms then just simple substraction gives the answer to the one without BT.
 
suavecarve said:
The next question to Garrys thoughts may be ....

If you have a Bluetooth lithium and a non Bluetooth one and they were the same size. Would the Bluetooth one give the same values on the app and would that equate to the non Bluetooth one? Ie would they charge equally ?
Click to expand...

You’re getting it…😉 wired in parallel + off one and - off the other.

To clarify if the battery with Bluetooth for example was reading 75% full would the dumb also be 75%…?
 
Raul said:
If they been together as a bank for few cycles yes. I found mine after 4-5 cycles to contribute very close to equal to their capacity. Reading the amps on the shunt as total, and the amps on the BT bms then just simple substraction gives the answer to the one without BT.
Click to expand...

Yes Raul, bought new as a pair and run as one large battery is it safe to say that whatever the state of the Bluetooth battery the dumb battery should behave the same and be in a state of charge or depleted as the Bluetooth one…

You lot type faster then me….😆
 
So if I was to buy a 280ah Bluetooth lithium battery and a 280ah (same make) dumb lithium battery around £150 less it would be like having one big 560ah battery the Bluetooth readings I would be getting, after some time would be or could be the same in both batteries…🤔
 
good question, I asked bard to see what it thought,. Whether the answer below is correct I'm unsure.
‐---------
In theory, the Bluetooth in one battery should give readings and results for both batteries when connected in parallel, but it might not be perfectly accurate. Here's why:

Parallel Connection: When batteries are connected in parallel, their voltages are the same, and their capacities are added together. This means the Bluetooth-enabled battery's monitoring system will see the combined voltage of both batteries.
Current Distribution: However, the current drawn from each battery might not be perfectly balanced due to slight variations in internal resistance or other factors. This could lead to one battery discharging slightly more than the other, which the Bluetooth monitor might not fully reflect.
State of Charge (SOC) Calculation: The Bluetooth monitor typically calculates SOC based on voltage, current, and other parameters. Since it's monitoring the combined voltage, the SOC reading might be an average for both batteries, not the individual SOC of each.
Potential Issues and Considerations:

Accuracy: The SOC reading might not be as accurate as having Bluetooth monitoring in both batteries.
Battery Health: If one battery has a significantly different capacity or health than the other, it could affect the overall performance and lifespan of the battery bank. The Bluetooth monitor might not detect this imbalance.
BMS Compatibility: Ensure both batteries have compatible Battery Management Systems (BMS) to avoid any issues with charging or discharging.
Recommendation:

For the most accurate readings and to ensure balanced battery health, it's generally recommended to have Bluetooth monitoring in each battery when connecting them in parallel. This allows you to monitor the individual performance of each battery and identify any potential issues early on.

Additional Tips:

Use high-quality cables and connections to minimize resistance and ensure balanced current flow.
Periodically check the voltage of each battery individually to ensure they are balanced.
Consider using a battery balancer to further equalize the charge and discharge of both batteries.
By following these tips, you can maximize the performance and lifespan of your lithium battery bank.

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Tombola said:
good question, I asked bard to see what it thought,. Whether the answer below is correct I'm unsure.
‐---------
In theory, the Bluetooth in one battery should give readings and results for both batteries when connected in parallel, but it might not be perfectly accurate. Here's why:

Parallel Connection: When batteries are connected in parallel, their voltages are the same, and their capacities are added together. This means the Bluetooth-enabled battery's monitoring system will see the combined voltage of both batteries.
Current Distribution: However, the current drawn from each battery might not be perfectly balanced due to slight variations in internal resistance or other factors. This could lead to one battery discharging slightly more than the other, which the Bluetooth monitor might not fully reflect.
State of Charge (SOC) Calculation: The Bluetooth monitor typically calculates SOC based on voltage, current, and other parameters. Since it's monitoring the combined voltage, the SOC reading might be an average for both batteries, not the individual SOC of each.
Potential Issues and Considerations:

Accuracy: The SOC reading might not be as accurate as having Bluetooth monitoring in both batteries.
Battery Health: If one battery has a significantly different capacity or health than the other, it could affect the overall performance and lifespan of the battery bank. The Bluetooth monitor might not detect this imbalance.
BMS Compatibility: Ensure both batteries have compatible Battery Management Systems (BMS) to avoid any issues with charging or discharging.
Recommendation:

For the most accurate readings and to ensure balanced battery health, it's generally recommended to have Bluetooth monitoring in each battery when connecting them in parallel. This allows you to monitor the individual performance of each battery and identify any potential issues early on.

Additional Tips:

Use high-quality cables and connections to minimize resistance and ensure balanced current flow.
Periodically check the voltage of each battery individually to ensure they are balanced.
Consider using a battery balancer to further equalize the charge and discharge of both batteries.
By following these tips, you can maximize the performance and lifespan of your lithium battery bank.
Click to expand...

I like this, but the dumb battery will have a bms in it, just not Bluetooth….🤔
 
Tombola said:
Consider using a battery balancer to further equalize the charge and discharge of both batteries.
Click to expand...
The worst thing you can do, each battery is managed by its own bms, and NO additional balance is needed, you will actually imbalance the pack. Let each battery draw and absorb by its own ability.
As long as reasonable care is considered in regards to the cables, nothing else is needed.
 
Lenny HB said:
In theory yes but not guaranteed.
Click to expand...
It doesn't have to be 100% all the time, but as the draw/consumption is not linear neither the charge rate, there will be blip times when the current may not be equal, and most of the time the current WILL level of to equal values. Specially on float and low draw.
Also at each end of absorb cycle they will be balanced pretty well, ready for a new cycle.
Nothing to be scared of, been doing it for few years now, and I'm confident that each battery will work happily along another without comms. 👍
 

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