Lithium battery replacement for Gemini garage doors?

[L0uisc]

I'm looking for a Lithium (most likely LiFePO4 would be best) drop-in replacement for this Gemini garage door battery. I don't find anything in the physical dimensions of this battery. Am I missing something?

If something like this doesn't exist, I'm willing to do some R&D to develop one and sell it. How many of you would be interested to buy something like this?

 

[capd]

Just wondering how a lithium battery would be advantageous for a garage door? Does it get used all the time?

 

[ebendl]

Just wondering how a lithium battery would be advantageous for a garage door? Does it get used all the time?

Loadshedding?

Most common way that these things get broken - open/close the door while loadshedding is there, and between sessions there's not enough time to recharge the battery fully, so next loadshedding session it goes even lower and eventually the battery is drawn too low.

 

[capd]

Loadshedding?

Most common way that these things get broken - open/close the door while loadshedding is there, and between sessions there's not enough time to recharge the battery fully, so next loadshedding session it goes even lower and eventually the battery is drawn too low.

Which is why I ask if the garage is being used all the time i.e. draining the battery heavily during load-shedding – which would suit lithium.

Otherwise if there’s something I don’t understand, how would lithium be advantageous for a garage door seldom used during load-shedding and thus being charged fully always? Surely lead-acid would be better here.

 

[Paul_S]

Which is why I ask if the garage is being used all the time i.e. draining the battery heavily during load-shedding – which would suit lithium.

Otherwise if there’s something I don’t understand, how would lithium be advantageous for a garage door seldom used during load-shedding and thus being charged fully always? Surely lead-acid would be better here.

Lithium based batteries require a different charge technique to lead acid so unless you plan to add a new charge circuit you'll end up with suboptimal performance from lithium batteries.

 

[wingnut771]

Lithium based batteries require a different charge technique to lead acid so unless you plan to add a new charge circuit you'll end up with suboptimal performance from lithium batteries.

If you want to squeeze every last Wh out of it yes, otherwise a LA charger will be just fine and battery will live 10 times longer than a LA.

 

[Speedster]

Blue Nova?

 

[Not_original]

Which is why I ask if the garage is being used all the time i.e. draining the battery heavily during load-shedding – which would suit lithium.

Otherwise if there’s something I don’t understand, how would lithium be advantageous for a garage door seldom used during load-shedding and thus being charged fully always? Surely lead-acid would be better here.

Those 7ah cells are generally shitty. Knowing very little about garagedoors but enough about batteries in general, I'd say the door is just pushing 13. 7V and the battery trickle charges constantly. Problem is turning that into a lithium charger will need you to go through a seperate charging circuit, which can deal with the fact that it is being supplied from the very source it needs to power. Never really searched for those but I guess there will be charging boards able to handle this.. Easiest would offcourse be to cut the power to the supply completely and have it feed into a dedicated charging circuit with the batteries then feeding the unit directly via the battery terminals. You'd have to install a "battery depleted" cutout between the battery and unit to prevent overdischarge though

 

[Tim_vb]

Have a look at this battery from BlueNova. Looks like a drop in replacement with a BMS that handles the charging side

BN13V-8-104Wh

 

[ebendl]

Have a look at this battery from BlueNova. Looks like a drop in replacement with a BMS that handles the charging side

BN13V-8-104Wh

That's right - I've seen some people use the BlueNova in cheap UPS's as well as in gate motors. Haven't used it myself but in principle they should just work where the old 12v lead-cells used to work.

 

[agentrfr]

I'm looking for a Lithium (most likely LiFePO4 would be best) drop-in replacement for this Gemini garage door battery. I don't find anything in the physical dimensions of this battery. Am I missing something?

If something like this doesn't exist, I'm willing to do some R&D to develop one and sell it. How many of you would be interested to buy something like this?

DO NOT USE A LITHIUM IRON PHOSPHATE BATTERY FOR THIS PURPOSE

At best you should never draw more than 1C from a LiFe for more than a few (ie. 2 or 3) seconds. Your garage motor will pull in excess of 10 amps readily, which means you would need at least 20Ah size LiFe batteries (maybe even bigger).

Rather, buy 7Ah or 24Ah Lead Acid batteries, hot glue them somewhere convenient and use decently thick wires to extend out of the battery bay of the garage motor.

I can send you a photo what I have done for my one later if you need inspiration

 

[Tim_vb]

DO NOT USE A LITHIUM IRON PHOSPHATE BATTERY FOR THIS PURPOSE

At best you should never draw more than 1C from a LiFe for more than a few (ie. 2 or 3) seconds. Your garage motor will pull in excess of 10 amps readily, which means you would need at least 20Ah size LiFe batteries (maybe even bigger).

Rather, buy 7Ah or 24Ah Lead Acid batteries, hot glue them somewhere convenient and use decently thick wires to extend out of the battery bay of the garage motor.

I can send you a photo what I have done for my one later if you need inspiration

Centurion D5 Motor uses 13A at 24 V
BN13V-8-104Wh has a 30s discharge of 7A for 30s
BN13V-11-140Wh has a 30s discharge of 20A for 30s

However series (not parallel) operation of these batteries and their BMS may be an issue

 

[agentrfr]

Centurion D5 Motor uses 13A at 24 V
BN13V-8-104Wh has a 30s discharge of 7A for 30s
BN13V-11-140Wh has a 30s discharge of 20A for 30s

However parallel operation of these batteries and their BMS may be an issue

Yeah no, you cant series the batteries unless their BMSes can communicate with each other and know that they are in series (and in which order)

Also, OP would need to use two of the 11Ah batteries for the current draw, which is like R1150 each battery

Much easier to just do two 7Ah lead acid batteries methinks (~R300 each)

 

[L0uisc]

Have a look at this battery from BlueNova. Looks like a drop in replacement with a BMS that handles the charging side

BN13V-8-104Wh

I have looked at it, unfortunately it is not in the right size. It is too big to fit in the space left for battery in the Gemini garage door openers.

 

[L0uisc]

Those 7ah cells are generally shitty. Knowing very little about garagedoors but enough about batteries in general, I'd say the door is just pushing 13. 7V and the battery trickle charges constantly. Problem is turning that into a lithium charger will need you to go through a seperate charging circuit, which can deal with the fact that it is being supplied from the very source it needs to power. Never really searched for those but I guess there will be charging boards able to handle this.. Easiest would offcourse be to cut the power to the supply completely and have it feed into a dedicated charging circuit with the batteries then feeding the unit directly via the battery terminals. You'd have to install a "battery depleted" cutout between the battery and unit to prevent overdischarge though

Yes, as far as I can tell that is exactly what happens.

 

[L0uisc]

Just wondering how a lithium battery would be advantageous for a garage door? Does it get used all the time?

Battery life. Those lead-acid batteries don't last.

 

[L0uisc]

DO NOT USE A LITHIUM IRON PHOSPHATE BATTERY FOR THIS PURPOSE

At best you should never draw more than 1C from a LiFe for more than a few (ie. 2 or 3) seconds. Your garage motor will pull in excess of 10 amps readily, which means you would need at least 20Ah size LiFe batteries (maybe even bigger).

Rather, buy 7Ah or 24Ah Lead Acid batteries, hot glue them somewhere convenient and use decently thick wires to extend out of the battery bay of the garage motor.

I can send you a photo what I have done for my one later if you need inspiration

The motor is rated at <=4.5 A under load. I can't find the max discharge current rating for the original batteries.

A quick look around made me aware of some LiFePO4 cells with extra high C ratings. That might also be an option.

 

[L0uisc]

@agentrfr this LiFePO4 cell is rated at 46A max continuous discharge current at 2300 mAh capacity. I think one need to select the right cell, but there are LiFePO4 options which can handle the discharge current of my application.

 

[Magnum]

I'm looking for a Lithium (most likely LiFePO4 would be best) drop-in replacement for this Gemini garage door battery. I don't find anything in the physical dimensions of this battery. Am I missing something?

If something like this doesn't exist, I'm willing to do some R&D to develop one and sell it. How many of you would be interested to buy something like this?

I understand the Move towards a longer life Batttery. Lithium is a Different Animal. If you do not need it rather Stay away.

Had another Lithium Fire at work. I have become somewhat of an expert. If it starts to smoke you RUN!

 

[L0uisc]

I understand the Move towards a longer life Batttery. Lithium is a Different Animal. If you do not need it rather Stay away.

Had another Lithium Fire at work. I have become somewhat of an expert. If it starts to smoke you RUN!

LiFePO4? Because AFAICT LiFePO4's main selling point is that it's almost as good as Li-ion in terms of energy density, but much safer. Which is part of the reason why I wanted to go with them. (The other part being they are 3.2V nominal, not 3.6 or 3.7V, so it is easier to get something in the line of a 12V battery with them.)