Batteries for a newby

[John chamney]

Thanks Adam very similar to the Lucas brand batteries

[jwwirds]

For the Sherman I have bought a Liontron 20 Ah 24 v LiFePO4 battery. I am in the process of testing the electronic layout. I have connected the charger to the battery and nothing happens. When I measure the voltage on the terminals with no leads connected the voltage is zero. On the charger leads the voltage is 28,8 volt. Does anyone now what could be the cause of this? Could it be the BMS?

[Søren Sandvold]

Quick question: what kind of peak power in A, must the BMS be able to handle befire it shuts down? In other words, what kind of peak Amps does the motors pull from the battery? In this my case a Tiger 1.
TIA

[Christoffer Ahlfors]

I suggest you look at the main fuse. The batteries should have a rated discharge current equal to or above that to be on the safe side,.
If there is a BMS, it will protect the battery and it will be perfectly safe with a lower rating, but might get annoying if too low for your driving habits...

[Gerhard Michel]

Well, all my models are equipped with telemetry. So I can see also the peak current consumption of the motors on my transmitter display. My heaviest tank is a non Armortek Porsche turret Könisgtiger with about 160 kgs, 2 x 500 watt motors and steel track links. It consumes up to 65 A peak current, but also the Armortek Jagdpanther with Vincent's steel track links consumes up to 45 A when table turning on rough grounds (the original track links may cause some less power consumption). Driving straight forward in plain grounds all my tanks consume only 3 to 5 A. My Königstiger tows a car straight forward on plain grounds with only 28 to 40 A when rolling steadily. So a simple table turn can cost much more power than towing a car! Therefore the operating conditions are very important when planning the electric equipment. Many BMS are a little tricky because they stop the tank also when the current exceeds the limit for a very short time.

Therefore only one of my models, the Bigtanks Königstiger at about 100 kgs, is equipped with a BMS. I chose a 100 A BMS which is far strong enough for all imaginable operating conditions. I think a 50 A BMS could also do the job in 99 %. My other tanks work without a BMS and can't cause such problems. A simple 80 A automatic fuse does the job very well, but a single cell voltage monitoring is essential.

[Robert Kovacs]

Hi!

My question would be, have you thought about this battery?
It has a built-in BMS.
https://www.nootica.com/lithium-battery ... -50ah.html

Is it worth buying a monitor? What can you recommend?
https://www.intellitecmv.com/collection ... or-bmv-700

Thank you

[Chris Hall]

This post seems to have gone a bit astray and not really answering the question I asked .

John -

It’s not a simple question, so there isn’t a simple answer.

I suspect we all started with 2x 12v lead acid batteries. But they’re bulky and heavy, and deteriorate quite quickly. Remember that our tanks are heavy, and need a lot of power to move around, let alone sound, turret rotation, gun recoil …… so people are exploring more modern alternatives.

A simple question is: what do you intend to do with your tank when you’ve finished it ? If you’re just going to run it around the garden then lead acid is fine. But if you’re going to take it to shows, especially multi-day ones like TankFest (where you would be welcomed !) you might wish to consider a more robust solution.

All the best,

Chris

[jwwirds]

For the Sherman I have bought a Liontron 20 Ah 24 v LiFePO4 battery. I am in the process of testing the electronic layout. I have connected the charger to the battery and nothing happens. When I measure the voltage on the terminals with no leads connected the voltage is zero. On the charger leads the voltage is 28,8 volt. Does anyone now what could be the cause of this? Could it be the BMS?

Well, the people I got the battery from cleared this up. Because it's a battery with a bluetooth connection to the BMS it shuts down when the voltage drops to low. The solution was to open the battery and charge briefly directly on the cells bypassing the BMS per the manual they sent me. This worked a treat.

[John chamney]

Chris

Thanks for a answer I can understand . Being new to this I thought asking the question I would get a simple answer and I could be on my merry way to the nearest battery shop . Having looked at Phil’s chieftain post I can quite easily identify the batteries used , it would be nice to see the alternative to this so I can make a price comparison. Although people are going on about alternatives Iam unsure as to which is a good brand what size and so on I should be looking at . Just call me lazy but if someone has gone through the process already am sure it will be with more knowledge than me . Thanks

John.
John -

It’s not a simple question, so there isn’t a simple answer.

I suspect we all started with 2x 12v lead acid batteries. But they’re bulky and heavy, and deteriorate quite quickly. Remember that our tanks are heavy, and need a lot of power to move around, let alone sound, turret rotation, gun recoil …… so people are exploring more modern alternatives.

A simple question is: what do you intend to do with your tank when you’ve finished it ? If you’re just going to run it around the garden then lead acid is fine. But if you’re going to take it to shows, especially multi-day ones like TankFest (where you would be welcomed !) you might wish to consider a more robust solution.

All the best,

Chris
[/quote]

[Donald Suttie]

What type and where do you get the chargers for the Sealed Lead Acid golf buggy batteries? (Lucas type)

[Adrian Harris]

I use 2 x Ctek MXS 5 chargers, which you can get from Amazon or Halfords.

Adrian.

[Gerhard Michel]

Hi!

My question would be, have you thought about this battery?
It has a built-in BMS.
https://www.nootica.com/lithium-battery ... -50ah.html

Is it worth buying a monitor? What can you recommend?
https://www.intellitecmv.com/collection ... or-bmv-700

Thank you

Hi Robert,

this battery is a little overdressed in capacity and price, I would say. LiFe cells can be discharged to nearly 100 %; therefore 25 to 35 Ah should be sufficient for a 'normal' use and are equivalent to 40 - 60 Ah SLAs being discharged only to 50 %.

I don't use fix installed voltage monitors. A simple multimeter does the job (and some more) and can also be used in the field. But I highly recommend a telemetry system to have monitoring and warnings quite on the transmitter display when driving.

[Robert Kovacs]

Hi!

My question would be, have you thought about this battery?
It has a built-in BMS.
https://www.nootica.com/lithium-battery ... -50ah.html

Is it worth buying a monitor? What can you recommend?
https://www.intellitecmv.com/collection ... or-bmv-700

Thank you

Hi Robert,

this battery is a little overdressed in capacity and price, I would say. LiFe cells can be discharged to nearly 100 %; therefore 25 to 35 Ah should be sufficient for a 'normal' use and are equivalent to 40 - 60 Ah SLAs being discharged only to 50 %.

I don't use fix installed voltage monitors. A simple multimeter does the job (and some more) and can also be used in the field. But I highly recommend a telemetry system to have monitoring and warnings quite on the transmitter display when driving.

Hi Gerhard

Thanks for the answers, can I still contact you if I need help?

[Chris Hall]

Chris

Thanks for a answer I can understand . Being new to this I thought asking the question I would get a simple answer and I could be on my merry way to the nearest battery shop . Having looked at Phil’s chieftain post I can quite easily identify the batteries used , it would be nice to see the alternative to this so I can make a price comparison. Although people are going on about alternatives Iam unsure as to which is a good brand what size and so on I should be looking at . Just call me lazy but if someone has gone through the process already am sure it will be with more knowledge than me . Thanks

John.

John -

Very roughly, LiFePO4 batteries are about 5 times the price of lead acid, but should last at least 5 times as long. So the choice is fairly cost-neutral - it depends on your available cash ! LiFePO4’s are smaller and lighter, which is also a consideration. And the ‘power curve’ (techy bit) is more consistent, ie. you get the same output until the battery runs out, whereas lead acid wear down gradually from the start.

Some people build their own LiFePO4’s from individual linked cells ….. no, me neither . After advice I went to tracer.com, and bought their 24v 16a battery. You’ll need a charger and connection lead as well.

But, as I said before, it all depends on what you want to do with your Chieftain. Remember that’s it’s one of Armortek’s biggest and more power-hungry models. Very impressive, though.

All the best,

Chris

[Gerhard Michel]

Hi!

My question would be, have you thought about this battery?
It has a built-in BMS.
https://www.nootica.com/lithium-battery ... -50ah.html

Is it worth buying a monitor? What can you recommend?
https://www.intellitecmv.com/collection ... or-bmv-700

Thank you

Hi Robert,

this battery is a little overdressed in capacity and price, I would say. LiFe cells can be discharged to nearly 100 %; therefore 25 to 35 Ah should be sufficient for a 'normal' use and are equivalent to 40 - 60 Ah SLAs being discharged only to 50 %.

I don't use fix installed voltage monitors. A simple multimeter does the job (and some more) and can also be used in the field. But I highly recommend a telemetry system to have monitoring and warnings quite on the transmitter display when driving.

Hi Gerhard

Thanks for the answers, can I still contact you if I need help?

Hi Robert,

of course you may contact me for hints to this topic.