Depends how "techy" you want to get and how cheap you want to be.
Optimate is good if you've got £50-£80 to spare and you want no hassle - just leave it connected.
I use a Lidl 500mA battery conditioner thing that cost £5. - I have it on a timer (1 hour a day)
It tops the battery up to 13.5V and then stops charging. For most purposes its as good as an optimate.
I used to use a standard car battery charger with a 10 ohm series resistor and monitored it with a voltmeter
(that cost £0.00)
Avoid:
- A car battery charger directly connected to the battery.
- Any charger or "trickle charger" for "small batteries" that doesn't self-limit at 13.5V (There are plenty out there )
- All solar battery chargers unless you KNOW that they cut off at 13.5V
(There is a lot of bollox talked about solar battery chargers - the phrase "current limited" is meaningless)
(Come to think of it ... there's a lot of bollox talked about battery chargers generally)
(But then ... there's a lot of bollox talked generally
)
