Forklift LiFePO4

[Luis Fernández]

Good Morning. I need help with a project that is giving me many headaches.
I am trying to change the batteries of a lead forklift for a LiFePO4, for this I need to connect a BMS (I already have one of the brand Elektromotus) but I do not know how to make the connections with some of the devices that already has the forklift .
For example: I need to carry a wire to a motor fan and to the BMS so that it manages it etc ...
I have the connection diagram provided by elektromotus, but I am insufficient, since I do not have all the necessary knowledge.
Someone can lend me a hand.
Thanks greetings.


I bring BMS photo in case it helps.

 

[Luis Fernández]

How and what do I need to change and run my forklift by replacing the old lead and water batteries with LiFePO4? BMS already have. For characteristics of 24v 370a / h what contactors, fuses etc ... would be suitable?

 

[shrtrnd]

I don't know the laws in your country, but in mine a forklift is serious business because of legal liability issues.
If you do something incorrectly and the forklift fails while in use, or a fire results, that's a serious legal problem.
If you do this yourself, then plug it in overnight to recharge, and a fire results, burning down your business, nobody
will be happy.
I'd contact the forklift manufacturer, tell then you want to change battery types, and see what suggestions they
have.

 

[Tha fios agaibh]

If the voltage is the same it shouldn't impact the internal components of your forklift.

Excellent point by shrtnd. I'll add that even if you are using a charger designed for your battery, the forklift is designed knowing the specific weight of a battery. Using a different battery (probably lighter) will change the counter balance of the machine and make it unstable when picking up loads.

 

[Luis Fernández]

Hello everyone.
I get a doubt, to see if anyone can help me.
If I have a HiFi traction battery charger I can use it without fear for LiFePO4 batteries, in case of failure the BMS and the BMS contactor would come on, or I need a new charger / unloader / balancer.
Thank you

 

[Luis Fernández]

Thanks for the comments and help.
The subject of the counterweight I already have it calculated, since in the chest where the batteries are, they fit 12 glasses, of which only 8 go with LiFePO4, the remaining 4 had thought to use them of counterbalance. Also in each glass of the 8 that I will use spare space to also put balance.
I still need some help especially about contactors to put, fuse, etc ...
Since I have clear that I will put at least 2 one to + and another to the - battery, plus a fuse to the positive battery.
I give graphic information in the attached photo.
Thanks again and I hope answers.

 

[Audioguru]

He wants somebody to look up what the charging specs are for a HiFi traction battery charger and see if the charging specs of the LiFePO4 battery he has are the same. Why doesn't he look the specs up himself?
What or who is "BMS"?

A LiFePO4 battery needs a charger designed for it.

 

[Tha fios agaibh]

I still need some help especially about contactors to put, fuse, etc ..

Why are you changing oem components if the supply voltage is the same?

 

[Luis Fernández]

Sorry, maybe I can not explain myself.
BMS stands for battery management system.
What I want to know is if with the old HiFi charger battery, it serves me or I need to buy a specific charger / unloader / balancer for the LiFePO4.
Thank you all.

 

[Luis Fernández]

I explained, apologies for the language. The circuit is mounted on the battery, it is to make a battery controller. I do not know if I explained well.
I would like to know what type of contactors to put that type of fuse etc ...
Greetings and thank you.

 

[Audioguru]

I think your "battery controller" is a battery charger circuit?
Your circuit is designed to charge a lead-acid battery. A LiFePO4 battery is completely different and needs to have a charger circuit that is designed for it to prevent the extremely dangerous lithium battery from exploding and/or catching on fire. A lithium battery also needs an additional circuit to sense its voltage and disconnect it when its voltage drops below a certain voltage.

I do not know what is a "contactor".

 

[BobK]

contactor = heavy duty relay.

Bob