Recommendations for battery charger/maintainer.

[Johnbmwz4]

I have both CTEK MX5 and the cheap Lidl one. I have 2 cars and didn’t want to spend loads of cash on 2 CTEKs. Both work great and the Lidl one has very long wires which reach to both terminals under the bonnet of the E89 unlike the CTEK. The only thing wrong with the Lidl if the power goes off you have to turn it back on again unlike the CTEK that turns itself back on to the last setting. I have had both chargers ( one at a time) charging my E89 for long periods with no issues at all.

[B21]

I have both CTEK MX5 and the cheap Lidl one. I have 2 cars and didn’t want to spend loads of cash on 2 CTEKs. Both work great and the Lidl one has very long wires which reach to both terminals under the bonnet of the E89 unlike the CTEK. The only thing wrong with the Lidl if the power goes off you have to turn it back on again unlike the CTEK that turns itself back on to the last setting. I have had both chargers ( one at a time) charging my E89 for long periods with no issues at all.

I ran a data logger on one of the Lidl ones and it charged the battery fine but once it reached capacity it trip off line and wouldn't recharge without explicitly being disconnected and reconnected..maybe I didn't wait long enough for it to re-charge..haven't tested the other one yet..

We have power drop outs quite often here (end of a long piece of damp string up the valley) so went belt n braces..since I go into the my new garage several times a week probably fairly academic..but we will see..

I'll try all three back to back over the winter..

[philip hedley]

I ended up buying an Einhell 4 amp smart charger, it has a dedicated AGM battery charging profile, the conditioning stage is selectable and there was £11 off the RRP at amazon. Some smart chargers don't have a dedicated AGM charging cycle (CTEK do) and the reconditioning cycle is not deselectable. Apparantly AGM batteries shouldn't be reconditioned. Einhell also recommend the battery is disconnected whilst charging to err on the side of caution.

[B21]

I ended up buying an Einhell 4 amp smart charger, it has a dedicated AGM battery charging profile, the conditioning stage is selectable and there was £11 off the RRP at amazon. Some smart chargers don't have a dedicated AGM charging cycle (CTEK do) and the reconditioning cycle is not deselectable. Apparantly AGM batteries shouldn't be reconditioned. Einhell also recommend the battery is disconnected whilst charging to err on the side of caution.

Repetitive charging the battery on an E89 whilst it’s off the car and /or via the battery terminals confuses the Intelligent Battery System IBS..resulting in incorrect charging profiles and failure to predict when load shedding should be applied.

If the battery charger has the possibility of damage to the car’s electronics it’s not really the charger for a car such as the E89 which is so sensitive in so many areas to correct battery capacity and it’s management.

In general for an E89 if you have reached the point where you are looking at having to recondition a battery it’s time to get a new one.