battery charger procedures

[viperpaki007]

Can any body tell me that what is the difference between the charging procedure of Lead Acid, Nicd and NiMH batteries...Is voltage sensing of battery enough for designing a battery charger or current limiting should also be incoporated. and if so what is the recommended current and voltage levels for different kinds of batteries.
I also need to to the what is the difference in charging procedures of Fast chargers, Trickle chargers and normal chargers.
I hope that you people will suggest me some answers...

 

[banjo]

This is a very deep and large topic. While it would seem simple on the surface, it is actually complicated by all the different battery types and chemistrys.
In a nutshell, you have to be concerned that the charging current does not either boil the electroyte or is so strong it warps the plates of the battery. Fast chargers have to have safe guards to protect the battery. Normal, slow chargers limit the current by design and therefore are simpler. However, what it costs you is charging time.

Below is a link to info on Lead-Acid batteries. Other families have other requirements so each will have to be handled as a unique case. The charge recommendations depend both on the chemical family that the battery belongs to and the actual manufacturer's spec that built the batteries.

Be careful, remember that cell phones and laptops have caught fire due to improper battery charging. These were Lithium Ion batteries.

**broken link removed**

 

[viperpaki007]

Thanks banjoo for the help...i have read the article but still i have some confusions ..
In the article graph explains four steps to charge the battery.. I need to know that the voltage mentioned in the graph is battery voltage or charger voltage?..
I am confused because In most of the battery charger circuits the battery charger voltage is maintained at a constant high voltage eg 14.1 volts for 12 volt lead acid....and the battery is charged with a constant current.....so if this voltage is held constant how can algo suggest that the battery charger voltage should be increased.
I think the voltage in algo is battery voltage not the battery charger voltage if i am right

Added after 4 minutes:

I have got another question
While charging a battery It is normally connected to a high voltage supply e.g 14.1 volts for 12V lead acid battery.battery charger algorithm suggest that we should measure the battery voltage to check the status of charge and jump to next stage.
How can we measure the voltage of the battery because while charging it is connected to a relatively high voltage supply and the voltage measured will be of the supply not the battery.

Added after 7 minutes:

suppose a battery is charged with a constant current charger of say 1A and 14.1 Volts DC. Initial battery voltage was less than 12 volts as it is discharged. Battery is connected with a 0.1 Ohm resistor in series with battery charger. now battery can take more current than 1A but battery charger limits the current to 1A. The voltage drop on the series 0.1 Ohm resistor will be 0.1 Volts ... What will be the voltage measured at the terminals of the battery in this condition ....i think it will be 14.1-0.1=14V...it will not be less than 12 volts(in the beginning of the process also)....... do tell me if i am right

Added after 1 minutes:

please do suggest me answers to above questions ....it will be very helpful..thanks