Hi!
I designed SLA battery charger with BQ24450, circuit is shown in the following figure 1.
battery voltage: 12V
battery capacity: 65Ah
pre-charge current Ipre=0.02A
maximum charge current Imax=5.0A
taper current Itaper=0.5A
Vth=10.8V
Vbi=13.68V
Vfloat=13.8V
Vboost=14.4V
Vrch=9.42V
figure 1) charge circuit
And charging current, battery voltage profiles are attached following too.
figure 2) charge I/V profile
figure 3) 0 ~ 25000 sec expanded profile
1) Charger output voltage(battery voltage, Vbat) does not reach to Vboost, 14.4V, only 14.0V.
2) Charging does not terminated, the charger continues to supply a low current.
In this state, if places a load on the battery, charger is supplying all the load current. (see figure 2)
3) I understand the operation of the charger, as shown below figure 4.
Am I misunderstanding about this?
figure 4) recharge sequence
4) BQ24450 is correct to operate as shown in Figure 2?
I look forward to hearing any advice about this.
thank you
Best regards
Kwon